Store level data in plist instead of Array

[kennycason]

Not 100% sure if I will do this, but it's a thought as I could store a more read-friendly format. i.e.

###################
#   ...  @  ...   #
# $$$  #####  $$$ #
##   ###   ###   ##
 ##  #       ##  #
  ####        ####

note: use a special character to handle cases where a box be placed on a goal from start.