Modify socket behavior to hide internals

[adamrankin]

As per discussion at NAMIC, modifying the socket send and receive functions to take a template argument of message class. Internally, the message class can be queried to calculate the size to send.

Additionally, the Receive function can be made smarter to receive the header and the body inside a single function call. This would lessen the burden on the client to know the internals of the protocol behavior (receive header, parse, receive variable body size).