MD5 Support Implementation Issues (Patreon)

MD5 support is partially working now (it still lacks some features), but there are two big issues with it.

First, it conflicts with the MDL renderer, making all MDL models be rendered at very wrong positions. See the MDL ogres on the second screenshot.

Second, MD5 models are very slow to render. I'll have to study ways to deeply optimize the MD5 rendering. If the bottleneck is in the skeletal animations, for example, other desired formats such as IQM can also have performance issues.