migrate phw's brdgrd code to Tor git repo

I think we removed all appropriate trac components for this sort of thing, so picking a related one.

We should make a brdgrd Torproject git repo, and let phw (who already has an ldap account) commit to it.

The code is currently at https://github.com/NullHypothesis/brdgrd

I've been asking huge bridge operators to set it up, so we should make it into something more official (plus that way more people will look at it).