Close #51 Close #73 Migration to Bootstrap 4

.babelrc.js

@@ -0,0 +1,15 @@
+module.exports = {
+  presets: [
+    [
+      '@babel/env',
+      {
+        loose  : true,
+        modules: false,
+        exclude: ['transform-typeof-symbol']
+      }
+    ]
+  ],
+  plugins: [
+    '@babel/proposal-object-rest-spread'
+  ]
+};

.eslintrc.json

@@ -0,0 +1,38 @@
+{
+  "extends": "airbnb-base",
+  "env": {
+    "browser": true,
+    "es6": true
+  },
+  "rules": {
+    "no-underscore-dangle": [
+      "off"
+    ],
+    "func-names": [
+      "off"
+    ],
+    "class-methods-use-this": [
+      "off"
+    ],
+    "max-len": [
+      "error",
+      120
+    ],
+    "brace-style": [
+      "error",
+      "stroustrup"
+    ],
+    "no-param-reassign": [
+      "error",
+      {
+        "props": false
+      }
+    ],
+    "key-spacing": [
+      "error",
+      {
+        "align": "colon"
+      }
+    ]
+  }
+}