Revert "Switch from Twitter Bootstrap to the Gumby framework"
There are far more tools for Twitter Bootstrap. I don't have time or experience to be reworking things for Gumby.

This reverts commit 11e4f58acf0f997ed418a55ab00d464baf01fc13, reversing
changes made to 5e21547f4260586a194feef7926379e954c9d9d9.