Merge pull request #138 from textpattern/greenkeeper/cross-env-5.2.0

Update cross-env to the latest version 🚀

Author: philwareham

package.json

@@ -19,7 +19,7 @@
   "devDependencies": {
     "autoprefixer": "8.6.3",
     "clean-webpack-plugin": "0.1.19",
-    "cross-env": "5.1.6",
+    "cross-env": "5.2.0",
     "css-loader": "0.28.11",
     "mini-css-extract-plugin": "0.4.0",
     "node-sass": "4.9.0",