Implemented each Node as a separate thread. Also, added receive data functionality to ReceiveNode.

Other notes:
* Using TCP for data transmission instead of UDP.
Concluded that since each node will forward / receive data regardless of 'role' that these are all nodes.

Their forwarding and receiving mechanisms will remain the same. The only distinguisher is the 'role' attribute given to each.
Added a Link connection between Nodes.
Added a simple data structure for routing entries.
Completed Node initialization.