chore(package): update node-sass to version 4.5.1

https://greenkeeper.io/

package.json

@@ -261,7 +261,7 @@
     "karma-sourcemap-loader": "0.3.7",
     "karma-webpack": "2.0.2",
     "mocha": "3.2.0",
-    "node-sass": "4.4.0",
+    "node-sass": "4.5.1",
     "po2json": "0.4.5",
     "postcss-loader": "1.3.2",
     "react-addons-test-utils": "15.4.1",