* src/input/input.c:
   + introduced input_item_t that is shared between the playlist/vlm and the input thread (contains input name, options, infos, etc...).
   + changed prototype of input_CreateThread() to input_thread_t *input_CreateThread( vlc_object_t *, input_item_t * ).
* ALL: use input_item_t and INPUT_ADD_INFO when necessary.