Import bsddialog 0.1 Utility and Library, fully refatorized, API stable,
manuals completed, easier to maintain and improve.
Update deps for new API:
add mixedgauge consts, delete __DECONST and add bsddialog_geterror()
info to avoid silent errors
* tzsetup
* kbdmap
* distextract
Differential Revision: https://reviews.freebsd.org/D34066
When running the installer, in particular disextract (which is so far
the only part converted to bsddialog), on serial console or vt100 or
actually any terminal without color support, it failed to start.
This change makes bsddialog fallback on the black and white theme.
This is incorporated in newer version of bsddialog which will be
imported soon.
PR: 261272
Reported by: thj
Differential Revision: https://reviews.freebsd.org/D33920