Revise header/protocol

[firepear]

• There is no reason to send the protocol every time, when we have stateful connections. The connect message should send the protocol version that the client is speaking, and then it should be ignored
• Request status, at the protocol level, should be indicated in the header. The byte currently used for protocol version can be used for this, resulting in minimal changes to existing code.

[firepear]

Working this and #64 together, as the basis for v0.37.

The base module and client have been overhauled. Starting work on the server, but not sure if I'll get it done tonight. Need to wrap my head around it again first, as it's more complex than the client and has more moving parts.

[firepear]

The protocol has been redesigned and the client updated, which leaves the rest as implementation details.

But before this can be closed, a standard hello/protocol version check message needs to be coded in on the client side, and a handler for it implemented on the server side

[firepear]

PROTOCHECK implemented client-side