Update 2.8

//Changes 2.8://
* Update to CB 1.5.2-R1.0
* Add multi-world support in databases
* Add multi-plugins spawns support : in this order :
BukkitWorldSpawn(default) < Multiverse-Core < EssentialsSpawn <
Authme(/authme setspawn)
* Add BCRYPT passwordhashing method
* Set the Email method to HTML ! you can now send html email correctly
:)
* Some fix with BungeeCord
* Some fix with inventory security ( i recommend you to disable
ProtectInventoryBeforeLogin if you encounter issues , all inventory
click method are now cancelled )
* Add a separate thread for /login command (enable multi-threading in
config file)
* Add a separate thead for /register command (enable multi-threading in
config file)
* Add isRegistered(String playerName) in the API
* Some other code reworks
* Some other debugs
* Re-Indent code