* fhandler.h (fhandler_tty_slave::archetype): Make public.

* fhandler.h (fhandler_tty_slave::archetype): Make public.
(report_tty_counts): New macro.  Use throughout for reporting tty use counts.
* dtable.cc (dtable::vfork_child_dup): Add debugging output for usecount
increment.  Increment open_fhs if appropriate.
(dtable::vfork_parent_restore): "Close" artificially bumped ctty.
(dtable::vfork_child_fixup): Close ctty since it was bumped prior to vfork.
Save open_fhs around close since the closing of these handles has no effect on
the console.
* fhandler_tty.cc (fhandler_tty_slave::open): Reorganize calls to allow for
easier tracking of usecount modification.
(fhandler_tty_slave::open): Ditto.