Thread Safety about hyper

[Lukasa]

I've thought a lot about this and haven't yet come up with a solution that both doesn't suck and doesn't require us to spin up our own threads (bad).

For the moment, then, my intended design will be that each Connection must be used from only one thread, and that users should sort out managing this as they see fit. This solves some of the problems.

I'll provide documentation for how to do this right (queues and locks being the main way).

[Lukasa]

I think this is no longer a valid concern, because of the plan to switch to asyncio (see #10), so I'm going to close this.