Spine 4.2 Physics support fix

Only works with Spine 4.2 exports

Fix (physics) correct update based on physics mode

Default is 'update'

Set to 'none' for no physics and less processing.

Add standard zElevation support

Add standard zElevation support (ACEs and property)

Update to 4.1.19 runtime

Update to 4.1.19 runtime (modified for C3, event data, global definition, https filter in atlas)
Fix renderquality action for 4.x assetmanager
Fix creating skeleton without defined skin

Add Load Files ACE, handle atlas with png file names as URL

Add Load Files ACE (can load files during runtime, set the properties to be blank to allow this, can only load once.)

To load remote files, the *.atlas file must be changed to use the corresponding URL for png files, not just the filename.

Fix addCustomSkinOutfit update slot colors for dependent colors

1.55.1

Add release 1.55.1

customSkinOutfit add dependent slot, separate skin tone support

1.55.0

feat (outfit) add custom skin outfit skin tone support

customSkinOutfit add dependent slot, separate skin and color

addCustomSkinOutfit(skinName, addOutfit, slots, dependentSlotsSkin, dependentSlotsColor)

Add expressions for bbox and scale properties

Add expressions for bbox and scale properties

feat (skin) add addCustomSkin script interface

feat (skin) add addCustomSkin script interface

addCustomSkin(skinName, addSkinName)

addCustomSkin('new-skin, 'hair/13')

addCustomSkinOutfit - ignore non-existent slots / blank skinName

Also, add Spine icon for the plug-in list.