Update .travis.yml

Author: kernelmethod

.travis.yml

@@ -21,6 +21,16 @@ jobs:
       os: linux
       script:
         -  julia --color=yes -e 'using Pkg; Pkg.activate(); Pkg.instantiate(); Pkg.test()'
+
+    ### Coverage
+    - stage: "Code coverage"
+      julia: 1.3
+      os: linux
+      script:
+        - julia -e 'using Pkg; Pkg.add("Coverage");'
+        - julia -e 'using Coverage; Coveralls.submit(Coveralls.process_folder());'
+        - julia -e 'using Coverage; Codecov.submit(Codecov.process_folder());'
+
     ### Documentation generation
     - stage: "Documentation"
       julia: 1.3