maintner: start of github polling

WIP; not functional yet, but submitting so
Kevin can continue if he wants.

Change-Id: I1dab38f9845ebcbd69ec2a6f07e98793d3ed7cfb
Reviewed-on: https://go-review.googlesource.com/37053
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
1 file changed