Minor update: Different scales for sprites

This is a minor update: Now besides the spritesheets and single sprites, the monsters are available in 2x, 3x, 4x and 5x scale as single sprites.

This is useful for game engines where you don't have easy ways to access sprite scale such as some versions of RPG Maker. 2x/3x scales are ideal for RPG Maker XP/Ace while 4x/5x are good for MV and beyond. (with default resolutions in mind.)

Thank you for your support!