chore(package): update rimraf to version 3.0.1

Closes #78

Author: greenkeeper[bot]

package.json

@@ -81,7 +81,7 @@
     "postcss-import": "^11.0.0",
     "postcss-loader": "^2.0.8",
     "postcss-url": "^7.2.1",
-    "rimraf": "^2.6.0",
+    "rimraf": "^3.0.1",
     "semver": "^5.3.0",
     "shelljs": "^0.7.6",
     "uglifyjs-webpack-plugin": "^1.3.0",