update devDependencies

Author: Foxandxss

package.json

@@ -30,7 +30,7 @@
     "css-loader": "^0.23.0",
     "extract-text-webpack-plugin": "^1.0.1",
     "file-loader": "^0.8.4",
-    "html-webpack-plugin": "^1.6.2",
+    "html-webpack-plugin": "^2.7.1",
     "isparta-instrumenter-loader": "^1.0.0",
     "jasmine-core": "^2.3.4",
     "karma": "^0.13.14",