CustomKits (CKits)

- Removed subcommands - insert, takeout, list, slots, getperm, withcost.
- Changed 'add' subcommand. Now it only takes in name.
- Added item view gui to see items that are contained in kit. You can also see permission if it has one. If player has ckits.admin permission, then he can also add/remove items and reset stock.
- 'stockreset' command now only resets all kits.
- Added 'set' subcommand with parameters:
        - 'needsPermission' - sets if player needs a permission to get kit,
        - 'cost' - replaced 'withcost' subcommand,
        - 'stock' - sets stock. For no stock use -1,
        - 'isLimited' - sets kit to be limited and 'cooldown' parameter to 0,
        - 'cooldown' - sets new cooldown and sets 'isLimited' parameter to false.