Added (stub) reply function.

  This is just a NOP.
  Added function to return the current message.

  This will either use the named path, or the currently selected
 message.
  More work on the reply() function.

  This is sketched out but incomplete, and it will segfault post-reply.
  Don't delete the message in reply().

  This causes a segfault.  When get_message_for_operation is called
 with a NULL argument the result must NOT be deleted, because it is
 a pointer to the global vector-entry.
  Quote message in reply() function.

  This needs to be a little more selectable.