bone51 & audio cape 

This branch merges in all patches from 3.8 kernel up to bone51, in addition to audio cape 2 support.

This stuff was collecting dust locally, and I remember it was a PITA to track which patches in the patchset corresponded to the commits in the bb kernel (hashes changed, branch got rebased, etc) so I decided to clean it up a bit and push it to github.