Fixes the sign prefix used on the first line
Makes TemporaryPermission comparable
Replaces some usage of OfflinePlayer with Player
Only removes a permissions if owned by the player
Adds a new thread that looks for expired temporary permissions
Adds the EconomyManager class for handling Vault payments
Adds the unfinished PermissionManager class for granting permissions through Vault
Adds the GPLv3 license
Fixes dependencies
Adds some code for withdrawing money and granting permissions when a sign is clicked
Changes cost to a double to be compliant with Vault
