Add option to create a new main.atlas file and new main.png sprite layout when saving.

[Seth-Revz]

Currently there are icons in the spritesheet that are used for multiple entries in main.atlas.
This creates the issue of if you replace these icons and they are different, keeping the same main.atlas will cause it to overwrite sprites.

Example:

The normal type monster icon is used for multiple languages.
You either overwrite for all, or none currently. They cannot be different

See the xy attributes below

monster_type_0_de
  rotate: false
  xy: 2, 4
  size: 49, 14
  orig: 49, 14
  offset: 0, 0
  index: -1
monster_type_0_en
  rotate: false
  xy: 2, 4
  size: 49, 14
  orig: 49, 14
  offset: 0, 0
  index: -1
monster_type_0_es
  rotate: false
  xy: 2, 4
  size: 49, 14
  orig: 49, 14
  offset: 0, 0
  index: -1
monster_type_0_fr
  rotate: false
  xy: 2, 4
  size: 49, 14
  orig: 49, 14
  offset: 0, 0
  index: -1