Bukkit

• Fixed deleteDatabase command.
• Added /xpRank online [n players] command. It shows a top list of online players.
• Added handing of ties where more players have the exact same xp values
• Implemented permissions which defaults to op and no-op if there is not permissions plugin.

Testing Needed:

• I need to test if the /xpRank online [n players] work when n players is smaller than the number of player currently online.