* Support immediate respawn gamerule
This commit now supports immediate respawn if the server enables it - both on the setting being applied on join and the setting being modified in-game. This also refactors the respawning process to more closely match BDS behavior - nothing broke in my testing but more testing is needed.
* Reuse spawned variable instead of creating new variable
* Implement helper methods for sending packets, fixes an NPE when chatting before connecting to the remote server
* Change method names
* Add a space between doc comment lines
* Add debug messages