Entity helper cleanup (#2505)
* Initial cleanup/update
* Update some code to pattern matching
* Cleanup `sendHide/ShowPacket`
* `look`: early return + pattern matching
* Remove redundant `yHeadRot` set in `setHeadAngle`
* Minor `internalLook` cleanup
* Update `getSourceFor` to modern switch syntax
* `getSourceFor`: add some missing sources
* Fix `BLOCK_EXPLOSION` handling
* Minor `getSourceFor` cleanups
* Use modern switch statements in `EntityHelper`
* Better `setFallingBlockType` param name
* Minor `damage` cleanup
Pattern matching, remove redundant variable
* `setUUID`: pattern matching, remove reflection
* Remove `TODO`
* Don't re-grab the instance in `setSneaking`
* use `CraftLocation#toBlockPosition`
* More `instanceof` pattern matching
* Correct param types
* Improve naming
* Meta fix
* `setUUID`: bring back `remove` reflection
* More `instanceof` pattern matching
* `setFallingBlockType`: don't need a `final` setter
* Add comment to `PLAYERLIST_REMOVE`
(
commit: 207edc3)
