Fix failing tests (#134)

CC: @addyosmani @SBoudrias @passy

I've been able to narrow down the problem to the model tests. From the commit and build history below/above, you can see that everything works fine without the model specs. I even increased the timeout but that effort was to no avail.

I'll dig into the model specs now but I'm opening this incase anyone knows what's wrong before I find it.

You can also view the build history [here](https://travis-ci.org/fayimora/generator-ember/builds).
Raw link: https://travis-ci.org/fayimora/generator-ember/builds

:bow: 

Cheers

Fixes #134