finally finished but not eating

Finally apply the patch sent by <Someone> in 11/2003 for slashem-Bugs-799278,
updated to match the current code and handle additional cases.  The fix
is brute force: always ensure nomovemsg is set when nomul is called with
a negative value.  I also scanned the code for places manually setting
multi negative, they all set nomovemsg.  It would be nice to have a function
that did the right thing, but there are several special cases and I was
not feeling creative.

src/dothrow.c

@@ -633,6 +633,7 @@ hurtle(dx, dy, range, verbose)
     if(!range || (!dx && !dy) || u.ustuck) return; /* paranoia */
 
     nomul(-range);
+    nomovemsg = 0;
     if (verbose)
 	You("%s in the opposite direction.", range > 1 ? "hurtle" : "float");
     /* if we're in the midst of shooting multiple projectiles, stop */