Fixes#156
githib issue #156 complains that "The Excalibur falls down the stairs,"
is using poor grammar despite the fact that the usual drop message is
"You drop the +0 Excalibur." I agree. Change it to be "Excalibur
falls down the stairs." (Drop message remains unchanged.)
While looking at that, I noticed that when knocking other items down
stairs, text was being appended to the formatted object name. It was
probably safe due to the space reserved for inserting a prefix while
formatting an object's name, which becomes available for a suffix
after that name has been copied into otransit_msg()'s local buffer,
but using a separate buffer is safer.
e8a8f142ae