Turn primary footer blue

Incorporates updated `guss-colours` and attendant updates to the header.

![screen shot 2014-08-07 at 17 07 38](https://cloud.githubusercontent.com/assets/867233/3844893/2814db32-1e4d-11e4-8b34-5c85b0da35b4.png)

is now

![screen shot 2014-08-07 at 17 08 00](https://cloud.githubusercontent.com/assets/867233/3844902/33cd64a8-1e4d-11e4-9b9a-fced3c1e1b3d.png)


yeah it’s actually crisper too:

![screen shot 2014-08-07 at 18 13 30](https://cloud.githubusercontent.com/assets/867233/3845782/2ec859c8-1e56-11e4-966f-05a3fbda201c.png)
![screen shot 2014-08-07 at 18 13 36](https://cloud.githubusercontent.com/assets/867233/3845784/327eac84-1e56-11e4-90ff-ace2e0e22e9c.png)