Added fix based on https://prototype.lighthouseapp.com/projects/8886-pro...

See ticket
https://prototype.lighthouseapp.com/projects/8886-prototype/tickets/3778-arrayentries-conflicts-with-es6-arrayprototypeentries

I noticed this conversation 

https://twitter.com/jdalton/status/401555633721180160

so I added a fix for any browser that has Array.entries implemented already