Update .travis.yml to latest versions of django

### What is the problem / feature ?

Testing on travis was towards old versions of django.

### How did it get fixed / implemented ?

Updated travis config to the latest versions of django.

### How can someone test / see it ?

Look at a travis build.

*Here is a cute animal picture for your troubles...*

![dog-pumpkin-9](https://cloud.githubusercontent.com/assets/824194/4760646/9f2fd18c-5af1-11e4-8538-8c84067256e9.jpg)