Modifications to the playqueue-clear command:

- do not stop playback when clearing the UpNext queue
- clear history, if mode=0x68697374 ("hist")

src/player.h

@@ -173,6 +173,9 @@ player_queue_remove(int ps_pos_remove);
 void
 player_queue_clear(void);
 
+void
+player_queue_empty(int clear_hist);
+
 void
 player_queue_plid(uint32_t plid);