Upgrade To Babel v7

src/client/.babelrc

@@ -1,3 +1,4 @@
 {
-  "presets": ["react"]
-}
+  "presets": ["@babel/react"],
+  "plugins": ["@babel/plugin-proposal-class-properties"]
+}

src/client/.eslintrc.json

@@ -1,8 +1,15 @@
 {
   "root": true,
   "parser": "babel-eslint",
-  "extends": ["plugin:react/recommended", "eslint:recommended", "google"],
-  "plugins": ["react"],
+  "extends": [
+    "plugin:react/recommended",
+    "eslint:recommended",
+    "google"
+  ],
+  "plugins": [
+    "babel",
+    "react"
+  ],
   "env": {
     "browser": true
   },
@@ -14,6 +21,12 @@
   "rules": {
     "import/prefer-default-export": 0,
     "no-console": 0,
-    "require-jsdoc" : 0
+    "require-jsdoc": 0,
+    "semi": [
+      2,
+      "never"
+    ],
+    "no-invalid-this": 0,
+    "babel/no-invalid-this": 1
   }
-}
+}