hero_seq

'moves' is actually turns and there hasn't been any straightforward
way to track actual hero moves.  Add hero_seq for that.  It isn't a
counter but is distinct each time the hero makes a move.  I wanted
it for curses ^P support but so far use it for checking stethoscope
usage and for shopkeeper behavior when items in a shop are broken by
the hero.

Increment EDITLEVEL due to change in save file contents.

include/context.h

@@ -135,8 +135,8 @@ struct context_info {
     int warnlevel;          /* threshold (digit) to warn about unseen mons */
     long next_attrib_check; /* next attribute check */
     long seer_turn;         /* when random clairvoyance will next kick in */
-    long stethoscope_move;  /* when a stethoscope was last used */
-    short stethoscope_movement; /* to track multiple moves on same turn */
+    long stethoscope_seq;   /* when a stethoscope was last used; first use
+                             * during a move takes no time, second uses move */
     boolean travel;  /* find way automatically to u.tx,u.ty */
     boolean travel1; /* first travel step */
     boolean forcefight;