Fixed possible deadlock during tree gen. Bunch more fixes.

Fixes #1306, #1313

* Fixed commands not working in eclipse console
* Fixed Cauldron debug logging.
* Added entity removal for entities with invalid locations during chunk
* load.
* Added missing GameMode used by FakePlayers in Bukkit API.
* Added new config option 'entities.skip-ticks-near-unloaded-chunks' which is disabled by default.
  - If set to false, it can help with performance at the expense of entity wandering into unloaded chunks and moveable chunkloaders.
* Moved config option 'world-settings.default.despawn-immediate' to 'world-settings.default.entities.despawn-immediate'
* Removed spawnEntityInWorld async check
* Catch invalid chunkpositions during Stronghold gen
* Cleaned up some code