MFC r328412: vt: add Ctrl+/ key mapping

This matches Xorg's handling of Ctrl+/ and may be useful as a tmux
escape.

PR: 212197
Submitted by: martin at sugioarto.com

MFC 321858: Add alternate Turkish keyboard layout F, submitted by Ufur Guler.
MFC 321859: While here, adjust a few file and path names in comments.

MFC r293047: Use correct name 'us' for character 31 in keymaps

'ns' was a historical accident, and kbdcontrol(1) has accepted the
correct 'us' as well as 'ns' since r38139.

PR: 205776

MFC INDEX.keymaps fixes

r282898: Correct UTF-8 encoding in Británico

One á was ISO 8859-1 0xE1 instead of UTF-8 0xC3 0xA1.

r282902: Correct language code -- "Danish" is English

The menu entry "Danish ISO-8859-1 (macbook)" was first added to the
syscons(4) INDEX.keymaps in r241851 with no language code, and then in
r256367 incorrectly tagged with "da". It is a Danish keyboard map, but
the description is in English and therefore must be "en".

This error subsequently propagated into the vt(4) INDEX.keymaps.

r282905: Restore 'he' language code for Hebrew kbdmap(1) menu title

r282914: kbdmap(1): Correct menu title: keyboards have a layout, not a language

PR: 146793, 193656

MFC r271452:

Add two forgotten keymap names (fr.kbd and fr.acc.kbd) to the list
of files to be installed.

Approved by: re

MFC improved vt(4) font generation

r266851: Add VGAROM 8x8, 8x14 and 8x16 fonts for vt(4)

These are converted from syscons(4) cp437 fonts.

r267306: Add vgarom font source

These are in 'GNU Unifont' format, and are converted from syscons(4)
cp437 fonts.

r267400: Add thin versions of VGAROM 8x8 and 8x16 fonts for vt(4)

These are converted from syscons(4) cp437-thin-8x* fonts.

r267423: Build vt(4) fonts during buildworld

vtfontcvt(8) is now built during buildworld, so can be used as a
bootstrap tool to create vt(4) fonts from source .hex or .bdf font
files, rather than having uuencoded binary fonts in the tree.

r267578: Add glyphs from converted syscons iso* fonts

This consists of the unique glyphs from the following font files in
/usr/share/syscons/fonts:

iso*.fnt ISO-8859-1 West European
iso02*.fnt ISO-8859-2 Central European
iso04*.fnt ISO-8859-4 Baltic
iso05*.fnt ISO-8859-5 Cyrillic
iso07*.fnt ISO-8859-7 Greek
iso08*.fnt ISO-8859-8 Hebrew
iso09*.fnt ISO-8859-9 Turkish
iso15*.fnt ISO-8859-15 West European

r268022: Rename the WITHOUT_VT_SUPPORT knob to WITHOUT_VT

The _SUPPORT knobs have a consistent meaning which differs from the
behaviour controlled by this knob. As the knob is opt-out and has not
appeared in a release the impact should be low.

Approved by: re
Sponsored by: The FreeBSD Foundation

MFC: 269950, 269952, 269973, 270114, 270119, 270142, 270156, 270200, 270229

Add fonts converted from SYSCONS with help of tools/tools/vt/keymaps
for use with NEWCONS. The mapping from SYSCONS name to NEWCONS name
is documented in KBDFILES.map in the tools directory.
A few of the files where modified by Ed Maste (ca.kbd, ca-fr.kbd).

MFC r267603 by trasz: Add polish vt(4) keymap.

Sponsored by: The FreeBSD Foundation

MFC: 266838 266841 267194
Add gallant vt(4) font as an example of font loading for vt(4).
Add Ukranian vt(4) keymaps as an example.

Sponsored by: The FreeBSD Foundation

Add gallant vt(4) font as an example of font loading for vt(4).

MFC after: 7 days
Sponsored by: The FreeBSD Foundation