chore(package): remove unused dependency file-loader

webpack plugin that isn't currently used (we use ts-loader atm)
close #474

package.json

@@ -70,7 +70,6 @@
     "eslint-plugin-node": "^8.0.0",
     "eslint-plugin-promise": "^4.0.1",
     "eslint-plugin-standard": "^4.0.0",
-    "file-loader": "^2.0.0",
     "html-webpack-plugin": "^3.2.0",
     "http-server": "^0.11.0",
     "jquery": "^3.2.1",