Server-client application with flexible data flow control.

Single threaded implementation of server-client networking model for data communication between 2 linux system. "transfer.h" specifies the function APIs available for use in an external application.
Starts with the role selection-server or client, and server starts sending a controlled flow of buffered data to client. The flow is interruptible through Linux Signals and exception handling. Currently configured for following 3 interrupts: 1)role-switch(server/client), 2)new buffer request from client, and 3)Flag-change based transmission of buffer from server to client.