adds new images for release, beta and canary builds
Merge pull request #1118 from twokul/new-builds-images

Adds new images for release, beta and canary builds (both retina and normal)
Add asknative to users list
Merge pull request #1119 from seifsallam/master

Add asknative to users list
Update fixture adapter docs to work with ember-data.beta.3
Merge pull request #1121 from bmac/fixture-adapter

Update fixture adapter docs to work with ember-data.beta.3