This is not an update for 1.13 support (yet). This one is mostly code clean up.
- Code is now set up with Maven, so if someone needs to fork/continue the plugin in the future it should be easier to do.
- More error and status messages.
- Improved sanity checks and the plugin should clean up after itself better.
The 1.13 support is in progress and seems to be working so far. However
https://bugs.mojang.com/browse/MC-125134 has made testing rather difficult as going out that far often triggers a server crash.