Button colours clean up

Some of the unused, default button colours have been changed to accommodate tags with no tonal colouring. 

Also slightly adjusted some of the tonal tag classes. 

// @ironsidevsquincy @paulrobertlloyd 

![screen shot 2014-10-03 at 14 12 59](https://cloud.githubusercontent.com/assets/2236852/4506097/09ed383c-4aff-11e4-86d8-8074a88180b5.png)