Merge pull request #10 from unshiftio/greenkeeper/assume-2.0.0

Update assume to the latest version 🚀

Author: 3rd-Eden

package.json

@@ -29,7 +29,7 @@
   },
   "homepage": "https://github.com/unshiftio/xhr-status",
   "devDependencies": {
-    "assume": "1.x.x",
+    "assume": "^2.0.0",
     "istanbul": "0.x.x",
     "mocha": "4.x.x",
     "pre-commit": "1.x.x"