enhancementhelp wanted
Description
This is happening!

This branch... https://github.com/garris/BackstopJS/tree/puppeteer
is tracking this branch... https://github.com/krisdigital/BackstopJS
Interested in contributing? ...please coordinate with @krisdigital.
What you need to know...
- The Puppeteer engine option will be released as soon as we are at feature parity with Chromy and Phantom.
- We will continue to support Phantom, Chromy and Puppeteer moving forward.
- You are awesome.