Brain

This is just a proposal. 

It simplify, and shorten the [MRI Interact](http://nbviewer.ipython.org/github/sburns/mrinteract/blob/master/mrinteract.ipynb) example to be less than 10 lines, by importing a module `brain_viewer` which is 25 lines long.

```
import matplotlib
matplotlib.rc('figure', figsize=(8,6))
%matplotlib inline

from brain_viewer import viewer

brain = 'MPRAGE.nii.gz' # this is a T1 image of my brain
viewer(brain)
```

I suppose we should ask the author authorization before showing his brain to the mass.