[ETF] Entity Texture Features

[V2.5.0] just in time for 40K downloads :)

• All of 1.18.x now in the one .jar file
• several optimizations and fixes
• cape support for Skin File Custom Capes , Minecraftcapes.net Capes & Optifine Capes
• fixes for slimes outer layer
• new mob texture property "blocks" so you can set a mob's texture based on the block it spawned on
• support for resource-packs to control blinking length and frequency per texture via a "texture_blink.properties" file
• option to 'thin' the Elytra model as its stretched strangely in vanilla
• Improved the skin feature guide