Render players with skin #57

For entity models, we can get this off of the default Bedrock resource pack.

• download: https://aka.ms/resourcepacktemplate
• github: https://github.com/ZtechNetwork/MCBVanillaResourcePack/tree/master/models

These can be automatically extracted and put into a bedrock-assets repo and referenced like minecraft-assets.

Documentation on the schema:

• https://minecraft.gamepedia.com/Tutorials/Changing_Minecraft_entity_models
• https://minecraft.gamepedia.com/Bedrock_Edition_schemas_documentation (under "geometry" section).

Existing parsers:

• https://github.com/JannisX11/blockbench/blob/master/js/io/formats/bedrock.js#L320
• https://github.com/kennyvv/Alex/blob/master/src/Alex/Graphics/Models/Entity/EntityModelRenderer.cs#L134 - Alex client also implements chests which may help solve #58