Revert Changes to Player Movement

Once and for all.

Thanks to Thinkofdeath & the users who put up with these changes, it was for a good cause, however at this point in time we do not feel it is possible to correct the large number of exploits present in player movement without the cooperation of Mojang. We will be seeking their cooperation, however in the mean time it is recommended that users install an anticheat plugin such as NoCheat+ to ensure some level of protection.

This will fix some strange behaviour users have been seeing in relation to player movements.
Build against the Spigot copy of minecraft-server
Tabs....
Fix Slow "Loading Libraries"
Revert Bukkit Damage API Behavior

This API is extremely broken and even updated plugins can not adequately restore their intended behavior with the existing API.

Until Bukkit comes up with an adequate solution, lets revert the change in behavior.

New plugins using the API will not error but will also not behave as intended, but there are likely no plugins using this new API.