Heart of Ahriman hack (trunk only)

From a four year old news posting:  hero was levitating via #invoke
on the Heart of Ahriman, then dropping that artifact yielded:
  You drop a gray stone named The Heart of Ahriman.
  You float gently to the floor.
  A gray stone named The Heart of Ahriman hits the floor.
That might be strictly correct, assuming that both hero and stone fall at
the same speed; if the stone was dropped from perhaps waist height then
the hero's feet would touch first.  But it looks strange, like a cartoon
where something hangs in midair until someone notices that it should fall.

     Removing the artifact from inventory causes the #invoke property to
toggle off.  Unfortunately it has to be done here before the object can
be placed at its destination.  Modifying message order seemed unviable;
this fix fiddles with the Levitation property in order to defer hero's
descent until after object handling is finished.  Now same setup gives:
  You drop a gray stone named The Heart of Ahriman.
  A gray stone named The Heart of Ahriman hits the floor.
  You float gently to the floor.
  You see here a gray stone named The Heart of Ahriman.

doc/fixes35.0

@@ -241,6 +241,7 @@ engulfer under influence of conflict or confusion could swallow monster at
 unicorn horn restoration no longer overrides sustain ability characteristic
 hider monster revived from corpse would start out hidden (even if own corpse
 	was only object around to hide under)
+fix sequencing issues with dropping #invoked Heart of Ahriman
 
 
 Platform- and/or Interface-Specific Fixes