Command repeating by using cmd queues

This replaces the old pushq/saveq arrays (which were used to save
the keys pressed by the user for repeating a previous command)
with a new command queue.  This means there's no hard-coded limit
to the saved keys, and it can repeat extended commands which are
not bound to any key.

src/hack.c

@@ -3571,7 +3571,7 @@ nomul(int nval)
     if (nval == 0)
         g.multi_reason = NULL, g.multireasonbuf[0] = '\0';
     end_running(TRUE);
-    cmdq_clear();
+    cmdq_clear(CQ_CANNED);
 }
 
 /* called when a non-movement, multi-turn action has completed */