Django 1.8 support

[jperelli]

This removes an annoying deprecationwarning in django 1.8.

I've also tested django 1.7 and 1.8, and the module works ok in both.

If you please could merge this and send it to pypi, it would be awesome.

Thanks!

[jperelli]

I'm trying to do the tests work in django >1.5. The problem is that the django structure to do tests is not working for django > 1.5 I can't get to load different tests structure for django >1.5