chore(package): update css-loader to version 0.26.0

https://greenkeeper.io/

Author: greenkeeper[bot]

package.json

@@ -50,7 +50,7 @@
     "core-js": "2.4.1",
     "coveralls": "2.11.15",
     "cross-env": "3.1.3",
-    "css-loader": "0.25.0",
+    "css-loader": "0.26.0",
     "extract-text-webpack-plugin": "2.0.0-beta.4",
     "file-loader": "0.9.0",
     "handlebars-loader": "1.4.0",