Merge pull request #2 from chocklymon/master

Add witches to the list of mob-spawns to block.
Added a better/combined entity remover. Added a namespace clear command.
[FrogWare] Prevent multiple starts.
Let's not damage horses that were set to negative ages.
Support xyz indexes in _relative(); (and added test version of _hologram)
[Teleports] Fixed falling through floors more reliably and with less threading.
[Timer] Prevent block break glitching/cheating.