Claim pricing modes & Various fixes

[Se7en-dev]

ADDITIONS :

Changed the current claiming price system and added 3 modes :

• ADDITIVE : Define the power needed for each claim with an additive factor.
• MULTIPLICATIVE : Define the power needed for each claim with a multiplicative factor.
• CUSTOM : Define the power needed for each individual claim. (This is the current claim system)

All 3 modes are detailed in the config file !

FIXES :

• Fixed the message that was sent when trying to execute commands from the console ("{prefix}" was shown instead of the actual prefix)
• Added error messages when trying to access the bank or war system when they are disabled in the config file. (Previously nothing was sent to the player, which caused confusion). Also added the error messages in all 3 .lang files