config(eslint): update config file format to JSON

the Hound GitHub extension only works with the .json config.

Author: joaopaulovieira

.eslintrc.js

@@ -0,0 +1,64 @@
+{
+  "env": {
+      "browser": true,
+      "commonjs": true,
+      "es6": true,
+      "node": true
+  },
+  "globals": {
+      "_gaq": false,
+      "process": false,
+      "ActiveXObject": false,
+      "VERSION": false,
+      "__dirname": false,
+      "after": false,
+      "afterEach": false,
+      "assert": false,
+      "before": false,
+      "beforeEach": false,
+      "describe": false,
+      "expect": false,
+      "it": false,
+      "sinon": false,
+      "xit": false,
+      "jest": false,
+      "test": false,
+      "module": false,
+      "require": false,
+      "CLAPPR_CORE_VERSION": false
+  },
+  "extends": "eslint:recommended",
+  "parserOptions": {
+      "sourceType": "module",
+      "ecmaVersion": 2018
+  },
+  "rules": {
+      "indent": [
+          "error",
+          2
+      ],
+      "linebreak-style": [
+          "error",
+          "unix"
+      ],
+      "quotes": [
+          "error",
+          "single"
+      ],
+      "semi": [
+          "error",
+          "never"
+      ],
+      "no-var": "error",
+      "block-spacing": "error",
+      "curly": ["error", "multi-or-nest", "consistent"],
+      "object-curly-spacing": ["error", "always"],
+      "brace-style": ["error", "1tbs", { "allowSingleLine": true }],
+      "keyword-spacing": "error",
+      "space-before-blocks": "error",
+      "arrow-spacing": "error",
+      "max-len": 0,
+      "max-statements": 0
+  }
+}
+