Tracker now passes unit tests

Tracker has some unexpected errors but now passes all unit tests.
Added first unit test for P2Pnode

Added P2PNode unit test for joinNetwork function
Updated design doc

Rewrote P2PNode section of design doc with what should be a more stable,
more easily testable, and more readable architecture.
Formatting fix

Frikkin' Markdown tables...
Further update to design doc

Changed P2PNode specifications to something that would make sense both
for testing AND implementation. Derp.
Rewrote P2PNodeTest

Attempting to rewrite the TrackerConnect test to match new design doc
specs.
Added P2PNode unit tests, filled out P2PNode

Added RequestNode and ConnectNode test cases for P2PNode, and created
function stubs in P2PNode.
All P2PNode unit tests complete!

Added HandleReceivedTracker, HandleReceivedNode, and PassOnSearchRequest
unit tests to P2PNode tests.