ENH: update logo

Rearranged a bit to add new institutions.

![institutions](https://cloud.githubusercontent.com/assets/1908618/4999139/b08dc41e-69df-11e4-9321-4fb70c012009.png)

In case someone wants to edit:

https://www.dropbox.com/s/vgf5w2dr8cf3v4w/logos_keys_09.key?dl=0

cc @agramfort