fix(package): update levelup to version 3.0.0

greenkeeper[bot] · greenkeeper[bot] · commit f3a4447bf91b · 2018-05-23T12:21:16.000Z
Closes #21
diff --git a/package.json b/package.json
@@ -31,7 +31,7 @@
     "fetch-ponyfill": "^4.0.0",
     "hsts": "^2.0.0",
     "leveldown": "^1.5.0",
-    "levelup": "^1.3.3",
+    "levelup": "^3.0.0",
     "morgan": "^1.7.0",
     "nocache": "^2.0.0",
     "solc": "^0.4.4",
