puzzleform update

- Fixed flickering when redrawing board by using BufferedGraphics
- Board is no longer marked as an optional parameter in PuzzleForm constructor
- UI appearance/layout changes
- GetTile method that returns board coordinates that touch a certain point (no longer static)
- Key/Mouse presses made will activate certain functions, including inputs to boardState (only if mouse touching board)
- Added input-handling abstract methods TileInput and TileClick to Board class

/ still missing solution for board not updating visually when boardState changes
/ solved 2 bugs by maximizing PuzzleForm window on start, removing this will make the bugs return
/ there is still at least one scenario where the input detection dies