chore(package): update file-loader to version 4.3.0

Closes #110

Author: greenkeeper[bot]

package.json

@@ -138,7 +138,7 @@
     "enzyme": "^3.0.0",
     "express": "^4.14.0",
     "extract-text-webpack-plugin": "^3.0.0",
-    "file-loader": "^1.1.5",
+    "file-loader": "^4.3.0",
     "html-webpack-plugin": "^2.24.1",
     "identity-obj-proxy": "^3.0.0",
     "jest": "^22.0.4",