Use Prettier JS (#5017)

* Adds prettier

* Run lint before tests

Author: flovilmart

.eslintrc.json

@@ -14,7 +14,7 @@
         "sourceType": "module"
     },
     "rules": {
-        "indent": ["error", 2],
+        "indent": ["error", 2, { "SwitchCase": 1 }],
         "linebreak-style": ["error", "unix"],
         "no-trailing-spaces": 2,
         "eol-last": 2,

.prettierrc

@@ -0,0 +1,3 @@
+semi: true
+trailingComma: "es5"
+singleQuote: true

.travis.yml

@@ -48,6 +48,7 @@ before_script:
 - silent=1 mongodb-runner --start
 - greenkeeper-lockfile-update
 script:
+- npm run lint
 - npm run coverage
 after_script:
 - greenkeeper-lockfile-upload