Tor build variant to support lightweight socks bridge
Many people lately have been trying to run bridges on tiny devices.
#2764 (moved) and #3292 (moved) are about the security tradeoffs there, but while we're waiting for insight, I think we should get closer to being able to build these things.
One of Dan's Stanford students basically set up a python socks proxy that pulled down the Tor consensus and forwarded your traffic into one of the Tor relays. Great. Except he doesn't parse the consensus very much, doesn't check its signatures, etc.
Rather than writing a separate tool that does that, we should make a way to build a Tor binary such that you get to reuse the consensus parsing and signature checking, so it will pull down the consensus for you and check it, but the rest of Tor is left out.
(Unless we can think of an even better way to do it, that is.)