Fix path loading when working with optifine data.

[RobertWHurst]

This PR updates CemFairy#transformPath to better handle transforming resource paths.

This includes a few major adjustments such as proper handling of parent path expressions ("..") as well as fixes the way resource paths are loaded from Optifine compatible resource packs containing cem data.

Likely fixes: #75, #72, #58, #56, and others.