Updating quaternion from euler tests

Hi,

These tests were failing silently, only showing on console, but throwing an exception makes the tests properly fail:

![screen shot 2013-08-13 at 12 56 39 am](https://f.cloud.github.com/assets/148319/953174/73e4fd9c-03ed-11e3-9347-22346aebfff2.png)

Cheers,
- Daniel