Merge pull request #46 from toboid/greenkeeper/concat-stream-2.0.0

Update concat-stream to the latest version 🚀

Author: toboid

package.json

@@ -19,7 +19,7 @@
   "devDependencies": {
     "chai": "^4.0.2",
     "chokidar-cli": "^1.2.0",
-    "concat-stream": "^1.5.1",
+    "concat-stream": "^2.0.0",
     "coveralls": "^3.0.0",
     "eslint": "^5.0.0",
     "eslint-config-toboid": "2.0.0",