emberjs/data — pull request #2104 by sly7-7 (2014-07-22 12:25:00+00:00)
Title: Update with normalize

I've also cherry picked [@rwjblue's PR](https://github.com/emberjs/data/pull/1791) even if I'm not sure if updatePayload is worth it.

I've done it considering [@bmac comment](https://github.com/emberjs/data/pull/2096#issuecomment-49619854)