Link-up between Gerrit & Github

[Patrick Venture]

The first meta-google patchset was pushed by Brad into github.
Interestingly, the second patchset which was merged into gerrit 3 days
ago still hasn't been automatically pushed into github.  It makes me
think there's some box we need to check or a setting to push.

Brad, can you dig into this please?  I don't have any permissions to
poke at it on Gerrit.

Patrick