chore(package): update nyc to version 11.6.0

Closes #246

Author: greenkeeper[bot]

package.json

@@ -55,7 +55,7 @@
     "jsdom": "9.9.0",
     "mocha": "3.2.0",
     "npm-run-all": "3.1.2",
-    "nyc": "^10.0.0",
+    "nyc": "^11.6.0",
     "prop-types": "^15.5.8",
     "react": "16.2.0",
     "react-addons-test-utils": "15.4.1",