Brainstorm about TrueVFS alternatives / workarounds

TrueVFS was the last remaining vestige of SLF4J in WorldEdit. As I don't think it's likely for their logging implementation from 2015 to update, I removed it in the SLF4J replacement branch. There are a few options:

- TrueVFS doesn't even distribute the shaded jar anymore. Make our own, make it available somewhere, and it can contain the shaded SLF4J + Log4J bridge
- Figure out a way to not depend on TrueVFS. This might include dropping support for esoteric ZIPs, figuring out some way to support `.tar.gz` files (which don't even have a directory in them)