HTTP Based Master Server + Multithreading

LJ's gonna come in here and say I fucked up the mutexes, huh?

There are 3 reasons for you to review and merge this...

1. HTTP means connections go through Cloudfare, so the address of mb.srb2.org isn't public.
2. No memory leaks from the decade old Master Server daemon.
3. Multithreading means the game does not hang if the Master Server is slow.

Also check out the public REST API.