first pass on tattoo layering
- 2 layers, 1 "base" layer which is fixed onto the player model, 1 which is edited during a painting session
- tattoo compositor merges the editing layer onto the base layer when exiting the menu or saving
- fade is applied to base layer, and baked into the png when merging downwards
- rads add fade to the base layer visually with a parameter, which is only baked in during a merge
- reworked to accomodate a separate player sending the tattoo edits to the other for saving (bc tattoo chair eventually)
- moved more code to serverside to allow for direct painting communication between 2 clients