GUI resizes upon new game

[Namdrib]

Looks like the grid alignment changes and each CellIcon is 1 pixel shorter both horizontally and vertically.
First game is fine, but every subsequent game is slightly smaller than the first.

Possibly something to do with the way Minesweeper.resetGame() rebuilding things

[Namdrib]

Got a bit of a hacky fix right now by immediately calling Minesweeper.resetGame() after setting up to force a resize to the correct size.

However, need to find a way to not have the incorrect size in the first place. And by extension, find out what's causing the problem.