Add tags to PlayerData + implement a notify-off tag.

Not sure this is that much final, but PlayerData can now carry tags.
NoCheatPlus.sendAdminNotify... will now check PlayerData for the
"notify_off" tag, as a preparation for a command to turn off
notifications.
Put commands on feet.

* Add a new base class for better sub-command handling also for
tab-completion (AbstractCommand).
* Alter package structure slightly, to group command-classes by purpose.
* Some renaming.
[COMMAND CHANGE] Remove delay feature from ncp ban/kick/tell/tempkick.

"ncp delay..." still is available.
Add command to turn notifications off and on again (per player).
Correct order of permission checking for the root command.
Use a filter permission to see if a player can use the root command.

The permission is set as child of all command permissions 
(sub commands of the root command). This is done in post enable to not
have to add it 100 times to the plugin.yml. Hopefully permission plugins
handle this right, superperms (permissions.yml) does.
Attempt to fix high jump effect (5) + survivalfly (step).
Set version to 3.9.3-RC for release on BukkitDev.
Set version to 3.9.4-DEV for further random changes.
Add hook versions to the "ncp version" command.
Add dedicated 1.5.2 module.
Prepare to use Material.hasGravity (...).
NCPCompatBukkit: Bukkit dependency to 1.5.2-R1.0.
Add Bukkit as dependency for CompatCBDev, update version to RBs.
[BLIND] Attempt to catch open inventories for portals and world changes.
Update metrics.
Lost update...
Change config path for protectplugins.
Make messages configurable for hiding plugins.
Optimize ColorUtil.

* Use ChatColor.translateAlternateColorCode
* Use more (still too) complicated but faster method for color removal.