chore(package): update nock to version 11.8.1

Closes #87

Author: greenkeeper[bot]

package.json

@@ -32,7 +32,7 @@
     "hubot": ">= 2.7",
     "memory-streams": "^0.1.0",
     "mocha": "~3.4.1",
-    "nock": "~9.0.6",
+    "nock": "~11.8.1",
     "power-assert": "~1.4.2",
     "sinon": "~2.3.0"
   },