Allow us to remove the Faction Core from our inventory with a command

If we don't want to place a core, having the core stuck in our inventory is annoying. It would be nice if you could use a command (either /f core, or a separate command) to remove the core from our inventory, then you can use /f core if you later decide you want to place a core. In addition, the core shouldn't automatically re-appear in your inventory if you claim more land, as that could get annoying.