Scheduler changes...
Merge branch 'KeirJames'
Jenkins you live?
Protocol cleanups.
Revert "Jenkins you live?"

This reverts commit 6593a0e73693e184ef8f24d610413632c2ef2806.
More protocol fixes/cleanups.
Keeping gamemode over reconnect is working again. :D
Allow 13w04a clients to connect.
Allow 13w02a and 13w03a to connect.
Some protocol cleanups.
Add debugging mode.
So the admin can decide if he wants the messages instead of the Bukkit
team assuming he won't.
Also damn useful to debug protocol errors.
Don't handle null packages.
Remove useless PacketHandler.adjustProtocol.
Hopefully fix a ConcurrentModificationException².
Some JavaDocs.
Remove some unused imports.
More JavaDocs².
Better ping handling.
No else after a return.
Include JavaDocs into the jar.
Build for Java 1.6