Add Cloud Vision API

[JustinBeckwith]

The Google Cloud Vision API recently went to beta. It would be great to add API support:
https://cloud.google.com/vision/docs/

There's an existing NPM module here:
https://github.com/tejitak/node-cloud-vision-api

[stephenplusplus]

Check it out! #1136 :)

[JustinBeckwith]

Great to see this coming along!