Another more of less big wave of patches is included within today's patch, fixing several issues and removing things that shouldn't have been.

• Mow supports Mooshroom cows
• Officially build for 1.16.4 (older builds and minecraft versions work perfectly though as we don't use NMS)
  
• CommandUtils (basically a class from PseudoCommands) removed as Bukkit already does what we want to do it
• Further anvil merge fixes
• Rainbow slam no longer spawns in 10000 particles within a single block
• Deprecated a few API methods
• More Javadocs!