CF: Jumping bug

[Rauli Ruohonen <raulir@voimax.voima.jkl.fi>]

There is a bug in jumping code (or is the bug in monster code, if 
monsters shouldn't jump?), which crashes crossfire with SIGSEGV.

There is a line in attempt_jump(object *pl), which uses pl->contr->something,
and with monsters pl->contr==NULL.. Sometimes it crashes in draw(), which
is called by stop_jump(). I think that monsters shouldn't jump at all 
(what use is it to them?), so I made the following patch:

--- skills.c.old        Fri Oct 11 11:08:05 1996
+++ skills.c    Thu Oct 10 17:25:11 1996
@@ -361,6 +361,7 @@
   * while jumping over them.  
   */ 
 
+  if(pl->type!=PLAYER) return(0);
   remove_ob(pl);
   SET_FLAG(pl,FLAG_FLYING);
   for(i=0;i<=spaces;i++) {