Now we can re-use the RPC method<->result code in the TcpServer side
which will face wallets. Phew! Took me long enough!
It's a minimal JSON-RPC protocol impl.. but it'll do.
The 1 nice bit is the Schema spec I came up with which more-or-less
works well enough as a first-pass validatior.
Further passes are needed in interested client code, but the initial
pass validation can be done in a thread so as to not waste the main
thread's time validating json or dict key presence/absense. Yay.
