Created a FigureType enum to handle, well, figure types

Updated code the relied on the original figureGrid to use the new
FigureType enum
Changed grid array to be height-primary (meaning grid[height][width]) to
make some of my for-loops easier to follow conceptually

+ Also moved away from using members directly and instead using getters
and setters if available.
Collapsing rows now works

+ Collapsing works like this:
-- Clear full row
-- Copy row above the now empty row into said empty row
-- Increment Y-position for each block object in new row
-- Keep doing that to the top of the board
+ It's a little slow, but it works