Upgrade the source to use ES6 syntax including classes, import and static properties (#679)

* Add babel transform-class-properties to have static class properties

* Upgrade Lexer and Parser files to use ES6 classes

* Update eslint max line length to 90 character (more indent because of using ES6 classes)

* Upgrade eslint and jasmin to support ES stage-2 features

* Use static properties to place constants near their functions

* Migrate all remaining sources to ES6 syntax

* Increase eslint max line length to 84

* Remove non-babelified endpoint in dev server.js

* Clean up server.js functions after removing browserified

* Make screenshotter not to use babel endpoint as we babelify everything now

.eslintrc

@@ -1,4 +1,5 @@
 {
+    "parser": "babel-eslint",
     "rules": {
         "arrow-spacing": 2,
         "brace-style": [2, "1tbs", { "allowSingleLine": true }],
@@ -14,7 +15,7 @@
         "indent": [2, 4, {"SwitchCase": 1}],
         "keyword-spacing": 2,
         "linebreak-style": [2, "unix"],
-        "max-len": [2, 80, 4, { "ignoreUrls": true, "ignorePattern": "\\brequire\\([\"']|eslint-disable" }],
+        "max-len": [2, 84, 4, { "ignoreUrls": true, "ignorePattern": "\\brequire\\([\"']|eslint-disable" }],
         "no-alert": 2,
         "no-array-constructor": 2,
         "no-console": 2,