* Starting to refactor test, adding http post to wallet sender
* Implemented ability to run servers on different ports (mostly for testing), and implemented ability to post http requests directly to receiving wallets
* Adding detailed instructions on running multiple servers on the same machine
* Changes to build.doc to outline server running process
* Removed unwanted debug statements
* WIP Local server testing framework evolution
* More refactoring of server pool, checked in because there's a problem
* Added server reference structure, and ability to return server references from tests cleanly
* Added simulate_parallel_mining test, which puts some artificial slowdown into test mining loops, and the difficulty can currently be watched in the log
* Removing the ServerRef structure placed in earlier and replaced with a ServerStats structure, that just returns relevant info about the Server state without exposing it to the world
