additional urgent messages

Now I've remembered why I didn't follow through with these back when
I originally laid the groundwork.  New urgent messages:

 having an item of armor be destroyed
 having weapon be grabbed by a monster's bullwhip
 becoming engulfed
 being grabbed by an eel
 subsequently being drowned by an eel
 dying of petrification
 turning into slime then dying due to genocide
 dying due to fatal illness

There are lots more candidates.

src/muse.c

@@ -2214,8 +2214,8 @@ use_misc(struct monst* mtmp)
                 pline("%s fails to wrap around %s.", The_whip, the_weapon);
                 return 1;
             }
-            pline("%s wraps around %s you're wielding!", The_whip,
-                  the_weapon);
+            urgent_pline("%s wraps around %s you're wielding!", The_whip,
+                         the_weapon);
             if (welded(obj)) {
                 pline("%s welded to your %s%c",
                       !is_plural(obj) ? "It is" : "They are", hand,