Connected GUI and Board elements

Major update, made main.py into main.pyw, made main.py class-based,
modified gui slightly to accommodate for new features, added several new
functions to main.main.
New Features:
- You can make a single move by typing "dank" into the box and clicking
"Move"
- The board shown is the board being simulated
- You can see black pieces when they are on black squares now