Added a page to display buttons and sets

Resolves #912

http://jenkins.buttonweavers.com:8080/job/buttonmen-AdmiralJota/342/

This also involved tweaking the python client a bit, so that should be tested too.
Do we like `dieTypes => array('X Swing')`?  It means that if you want to ID buttons that contain any kind of swing dice, you have to parse text to do that, which is never the right answer.  But maybe at the moment we don't want to do that.