chore(package): update nyc to version 12.0.1 (#77)

Author: greenkeeper[bot]

package.json

@@ -44,7 +44,7 @@
     "coveralls": "^3.0.0",
     "github-release-from-changelog": "^1.2.1",
     "npm-run-all": "^4.1.1",
-    "nyc": "^11.0.3",
+    "nyc": "^12.0.1",
     "rimraf": "^2.6.2",
     "tslint": "^5.8.0",
     "typescript": "~2.8.1"