SocketSession creates Receivables when it receives an header.
SocketSession sends the payload to the created Receivable.
SocketSession takes an Executor interface instead of a Session interface.
SocketSession now acts on the receivable, when it is fully received.
Receivable now has a get_payload_length member function.
SocketSession can now read several protocol objects
File is now a Deliverable too.
Utility function for creating headers.
Message is now a Deliverable
Use create_header in all Deliverables.
Client is a Deliverable