Export layers as separate sprite sheets.

[Snowdrama]

Is your feature request related to a problem? Please describe.
My game uses a paper doll system to use weapons and armor, and would like for the importer to be able to handle importing of a single file with paper doll layers so that I can do all my animation in a single aseprite file for easy editing and updating.

Describe the solution you'd like
There would be a checkbox on the importer that would be like "export layers as separate sprites" and checking the box and re-importing would have a sprite sheet per layer.

Describe alternatives you've considered
I guess the alternative would just be having to manually exporting the animations from aseprite, or like figuring out how to write a lua script to export each layer and animation tag as it's own sprite sheet and then manually slicing and creating all the animations in unity by hand.

Additional context
In this example I have an attack right tag, and I have a Player Hammer and Sword layers, but when using the unity aseprite importer, these layers are flattened into a single sprite per frame causing the sword and hammer to be visible at the same time, I'd like for the player, hammer, and sword layers to be separate sprite sheets/animations

So if it's Player.ase then it would export the images and animations like:

Player/Player_Sword.png
Player/Player_Sword_Attack_Down.anim
Player/Player_Sword_Attack_Left.anim
Player/Player_Sword_Attack_Right.anim
Player/Player_Sword_Attack_Up.anim

Player/Player_Hammer.png
Player/Player_Hammer_Attack_Down.anim
Player/Player_Hammer_Attack_Left.anim
Player/Player_Hammer_Attack_Right.anim
Player/Player_Hammer_Attack_Up.anim

Player/Player_Player.png
Player/Player_Player_Attack_Down.anim
Player/Player_Player_Attack_Left.anim
Player/Player_Player_Attack_Right.anim
Player/Player_Player_Attack_Up.anim