Fixed inconsistent type of hairstyle networking
Cleaned up the inventory handling

Things done:
 - Removed the equips table and added another column which keeps track about
   whether the item is equipped or not
 - Added a message to notify the client about failing equips instead of
   hardcoding to chat notification
 - Removed the move possibillity. It was a quite long function and our future
   idea of the inventory does not need any moves
 - Removed the inInventory and inEquipment parameters from chr_inv_count,
   but added a equipped key to the table that chr_get_inventory returns

This change makes equipped items still being in the inventory. This means
in-inventory triggers are still active! However it makes no sense to disable
this triggers during equipping since it will appear as still in the inventory
to the client.
Fixes from bjorns review