Finished Pawn-GameState interactions

Rebuilt System to work with GameState.java
Began work on PromotedPawn.java
Finished work on EmptyPiece.java
Removed Herobrine.

Todo: More Pieces.
Todo: Smoothen the edges.
Todo: Make test classes.
Todo: Remove bugs.
Todo: Find flaws.
Todo: Commence work on UI.
Todo: Remove Herobrine.