diff --git a/package-lock.json b/package-lock.json
index 82a9aa1..83e3c1a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
     "name": "openmath-js",
-    "version": "1.1.0",
+    "version": "1.2.0",
     "lockfileVersion": 1,
     "requires": true,
     "dependencies": {
@@ -1094,14 +1094,6 @@
             "dev": true,
             "requires": {
                 "lodash": "^4.17.10"
-            },
-            "dependencies": {
-                "lodash": {
-                    "version": "4.17.10",
-                    "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.10.tgz",
-                    "integrity": "sha512-UejweD1pDoXu+AD825lWwp4ZGtSwgnpZxb3JDViD7StjQz+Nb/6l093lx4OQ0foGWNRoc19mWy7BzL+UAK2iVg==",
-                    "dev": true
-                }
             }
         },
         "async-done": {
@@ -1408,7 +1400,7 @@
                 },
                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {
@@ -1531,7 +1523,7 @@
                 },
                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {
@@ -1766,7 +1758,7 @@
                 },
                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {
@@ -2141,7 +2133,7 @@
                 },
                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {
@@ -2224,7 +2216,8 @@
                 "ansi-regex": {
                     "version": "2.1.1",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "aproba": {
                     "version": "1.2.0",
@@ -2245,12 +2238,14 @@
                 "balanced-match": {
                     "version": "1.0.0",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "brace-expansion": {
                     "version": "1.1.11",
                     "bundled": true,
                     "dev": true,
+                    "optional": true,
                     "requires": {
                         "balanced-match": "^1.0.0",
                         "concat-map": "0.0.1"
@@ -2265,17 +2260,20 @@
                 "code-point-at": {
                     "version": "1.1.0",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "concat-map": {
                     "version": "0.0.1",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "console-control-strings": {
                     "version": "1.1.0",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "core-util-is": {
                     "version": "1.0.2",
@@ -2392,7 +2390,8 @@
                 "inherits": {
                     "version": "2.0.3",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "ini": {
                     "version": "1.3.5",
@@ -2404,6 +2403,7 @@
                     "version": "1.0.0",
                     "bundled": true,
                     "dev": true,
+                    "optional": true,
                     "requires": {
                         "number-is-nan": "^1.0.0"
                     }
@@ -2418,6 +2418,7 @@
                     "version": "3.0.4",
                     "bundled": true,
                     "dev": true,
+                    "optional": true,
                     "requires": {
                         "brace-expansion": "^1.1.7"
                     }
@@ -2425,12 +2426,14 @@
                 "minimist": {
                     "version": "0.0.8",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "minipass": {
                     "version": "2.2.4",
                     "bundled": true,
                     "dev": true,
+                    "optional": true,
                     "requires": {
                         "safe-buffer": "^5.1.1",
                         "yallist": "^3.0.0"
@@ -2449,6 +2452,7 @@
                     "version": "0.5.1",
                     "bundled": true,
                     "dev": true,
+                    "optional": true,
                     "requires": {
                         "minimist": "0.0.8"
                     }
@@ -2529,7 +2533,8 @@
                 "number-is-nan": {
                     "version": "1.0.1",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "object-assign": {
                     "version": "4.1.1",
@@ -2541,6 +2546,7 @@
                     "version": "1.4.0",
                     "bundled": true,
                     "dev": true,
+                    "optional": true,
                     "requires": {
                         "wrappy": "1"
                     }
@@ -2626,7 +2632,8 @@
                 "safe-buffer": {
                     "version": "5.1.1",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "safer-buffer": {
                     "version": "2.1.2",
@@ -2662,6 +2669,7 @@
                     "version": "1.0.2",
                     "bundled": true,
                     "dev": true,
+                    "optional": true,
                     "requires": {
                         "code-point-at": "^1.0.0",
                         "is-fullwidth-code-point": "^1.0.0",
@@ -2681,6 +2689,7 @@
                     "version": "3.0.1",
                     "bundled": true,
                     "dev": true,
+                    "optional": true,
                     "requires": {
                         "ansi-regex": "^2.0.0"
                     }
@@ -2724,12 +2733,14 @@
                 "wrappy": {
                     "version": "1.0.2",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 },
                 "yallist": {
                     "version": "3.0.2",
                     "bundled": true,
-                    "dev": true
+                    "dev": true,
+                    "optional": true
                 }
             }
         },
@@ -2757,11 +2768,6 @@
                         "minimatch": "~3.0.2"
                     }
                 },
-                "lodash": {
-                    "version": "4.17.10",
-                    "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.10.tgz",
-                    "integrity": "sha512-UejweD1pDoXu+AD825lWwp4ZGtSwgnpZxb3JDViD7StjQz+Nb/6l093lx4OQ0foGWNRoc19mWy7BzL+UAK2iVg=="
-                },
                 "minimatch": {
                     "version": "3.0.4",
                     "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-3.0.4.tgz",
@@ -2860,7 +2866,7 @@
                 },
                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {
@@ -3152,12 +3158,6 @@
                         "time-stamp": "^1.0.0"
                     }
                 },
-                "lodash": {
-                    "version": "4.17.10",
-                    "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.10.tgz",
-                    "integrity": "sha512-UejweD1pDoXu+AD825lWwp4ZGtSwgnpZxb3JDViD7StjQz+Nb/6l093lx4OQ0foGWNRoc19mWy7BzL+UAK2iVg==",
-                    "dev": true
-                },
                 "lodash.template": {
                     "version": "4.4.0",
                     "resolved": "https://registry.npmjs.org/lodash.template/-/lodash.template-4.4.0.tgz",
@@ -3703,7 +3703,7 @@
                 },
                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {
@@ -3775,10 +3775,9 @@
             }
         },
         "lodash": {
-            "version": "4.17.11",
-            "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.11.tgz",
-            "integrity": "sha512-cQKh8igo5QUhZ7lg38DYWAxMvjSAKG0A8wGSVimP07SIUEK2UO+arSRKbRZWtelMtN5V0Hkwh5ryOto/SshYIg==",
-            "dev": true
+            "version": "4.17.15",
+            "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.15.tgz",
+            "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A=="
         },
         "lodash._reinterpolate": {
             "version": "3.0.0",
@@ -4185,7 +4184,7 @@
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                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {
@@ -4447,7 +4446,7 @@
                 },
                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {
@@ -5445,7 +5444,7 @@
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                 "readable-stream": {
                     "version": "2.3.6",
-                    "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+                    "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
                     "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
                     "dev": true,
                     "requires": {