gyro work in progress (a checkin)
simulator now running in another thread.  still need to implement the 'asking for control' and 'send sensor messages' part
This merge is necessary so I can work on the code.

Merge branch 'master' of https://github.com/daemacles/ess
Merge branch 'master' into control_loop
Basic networking code is there.  TODO: implement sensor->JSON serdes and move the demo rocket control code to client.cpp
network works.  need to change sensor json message a little bit and update demo client