Level Select (Near Complete)

NOTE: INCOMPLETE COMMIT - REQUIRES FIX
LevelSelect added as default start.
Level nodes clickable, call loadlevel()
Loads level from text file with grid size and replenish, squidge and
random booleans.
Button now loads on gem grid creation.
Button removed on level complete, timer stops and new grid is no longer
created.
Test level node created.
Gem type variable added - Normal is default, matches only if normal.