Experimental solve for trust and abandonclaim commands
In previous versions, it was possible for a claim owner to modify a claim that was currently rented. This is no longer an option.
To achieve this, I had to modify the GriefPrevention plugin. Unitl those modifications are merged into the actual GriefPrevention plugin (if ever), it is required to use the provided GriefPrevention.jar file instead of the default GriefPrevention.