Buildbot update

Few changes you might find important:
- WDK builder has been added to scheduler. All trunk revisions are from now on built on
both gcc and wdk.
- Cameron-requested USB builder is added as well. This one, connected to usb-bringup-trunk
branch, is triggered manually from web interface. All builds are stored on diablo, so
team-members with ftp accounts on it can access the builds just as all other ones. Please
contact me if one needs an account.

Enjoy

-- 
With best regards
Caemyr