chore(package): update npm-check-updates to version 2.8.0 (#1085)

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -65,7 +65,7 @@
     "karma-sourcemap-loader": "~0.3.7",
     "lodash": "~4.14.0",
     "merge-stream": "~1.0.0",
-    "npm-check-updates": "~2.7.1",
+    "npm-check-updates": "~2.8.0",
     "proxy-middleware": "~0.15.0",
     "q": "~1.4.1",
     "semver": "~5.3.0",