TcpIpcModule: support multiple data buffers for send/receive

TcpIpcModule: support multiple data buffers for send/receive

This is a preparation to introduce asynchronous client notifications.

Having multiple buffers is required in these situations:
- a client is just creating a message and is about to send it
- a client notification is received, overwriting the clients message

or:
- a message was received, the client is just about to read the data from it
- a client notification is received, overwriting the clients message

To handle these situations, 1 sendBuffer and 2 separate receive buffer have been created.