item: imlemented selectable
interface: insert marker for initiative pass
combat: change data storage to map
menu: implemented get_selected

the userptr is now used to store a ptr to the item containing the
curses ITEM pointer. pointer_data_model was changed accordingly
character: made identifier an integer counter

name is not unique and thus a bad identifier
interface: added options for next and interrupts

currently crashes if list is empty (turn is done)