Merge pull request #552 from ember-fastboot/greenkeeper/chai-fs-2.0.0

Update chai-fs to the latest version 🚀

Author: kratiahuja

package.json

@@ -38,7 +38,7 @@
     "broccoli-asset-rev": "^2.4.5",
     "broccoli-test-helper": "^1.1.0",
     "chai": "^4.1.0",
-    "chai-fs": "^1.0.0",
+    "chai-fs": "^2.0.0",
     "co": "^4.6.0",
     "ember-ajax": "^3.0.0",
     "ember-cli": "~2.16.2",