[Feature request] Slim mc 1.8 model (AKA "Alex" model)

[AlexKurisu]

Please add support for mc 1.8+ skins that use slim model (AKA Alex model, female model). Currently there's no support for such skins neither in this mod nor in any other one.

[SmallJoker]

Same reply as in #75. There's currently no-one taking care of model design. If you (or someone else) has a model that can legally be used in this project, feel free to open a PR.