Created generic send and receive messages. Avoided using varying ports.
Port is now static throughout the whole distributed system, which means
that the application uses a single port (e.g. 4400) over all the
computers. 

This allows all of them to communicate with each other without having to
guess if it is 4400, 4401, 4402... etc.

Multicast broadcasting is implemented as well, instead of manually
broadcasting to IPs 192.168.10.100, 101, 102, 103.