Solve confilict between firebase library and app component & create index for firebase services folder to have a short path

package.json

@@ -71,11 +71,12 @@
     "babel-core": "^6.24.1",
     "babel-loader": "^7.1.2",
     "babel-plugin-transform-decorators-legacy": "^1.3.4",
-    "babel-polyfill": "^6.26.0", 
+    "babel-polyfill": "^6.26.0",
     "babel-preset-env": "^1.6.0",
     "babel-preset-react": "^6.24.1",
     "babel-preset-stage-0": "^6.24.1",
     "css-loader": "^0.28.7",
+    "eslint": "^4.9.0",
     "karma": "^1.6.0",
     "karma-chrome-launcher": "^2.0.0",
     "karma-mocha": "^1.3.0",