Enable basic command line editing in amd64 installer shells

When a user selects "exist installer" or hits ^Z in sysinst, the
calling install.sh runs a shell, plus shows a message indicating
they can type "exit" to return to the installer.

Add -E to the arguments to this shell, to enable command line editing,
(primarily for arrow keys, but basic emacs sequences will also work)

At this point this is only on amd64, as this is the port which is
least likely to be installing on particularly esoteric terminal
hardware, and is also likely to have the highest proportion of less
experienced users

Make sure to copy the language catalog files for sysinst, but do not
copy sysinst itself to / on the CD, and instead use the base version
for installation.

Switch device database to cdb(5). Rework ttyname(3) and ttyname_r(3) to
depend on new devname_r(3) as heart. Add /dev/pts magic directly to
devname(3). While it can lead to returning non-existing paths, the
behavior is more consistent that way. Drop caching layer in devname(3),
it doesn't buy anything for the common case of having access to the
database. Teach devname(3) proper fallback behavior of scanning /dev.
Create both old-style and new-style database for now in /etc/rc.d/sysdb.

branches: 1.2.4; 1.2.6;
On install CDs: make ^C and ^Z work (mostly) as they used to do on
crunched/ramdisk install media again.
Fixes the remaining parts of PR 44738.

Bring amd64 installation ISO to same state as the i386 one:
- GENERIC kernel for booting
- root is now cd0a
- use the same scripts and conf files as the i386 install ISO.

See also http://mail-index.netbsd.org/port-i386/2011/01/14/msg002247.html

Make sure to copy the language catalog files for sysinst, but do not
copy sysinst itself to / on the CD, and instead use the base version
for installation.

Switch device database to cdb(5). Rework ttyname(3) and ttyname_r(3) to
depend on new devname_r(3) as heart. Add /dev/pts magic directly to
devname(3). While it can lead to returning non-existing paths, the
behavior is more consistent that way. Drop caching layer in devname(3),
it doesn't buy anything for the common case of having access to the
database. Teach devname(3) proper fallback behavior of scanning /dev.
Create both old-style and new-style database for now in /etc/rc.d/sysdb.

branches: 1.2.4; 1.2.6;
On install CDs: make ^C and ^Z work (mostly) as they used to do on
crunched/ramdisk install media again.
Fixes the remaining parts of PR 44738.

Bring amd64 installation ISO to same state as the i386 one:
- GENERIC kernel for booting
- root is now cd0a
- use the same scripts and conf files as the i386 install ISO.

See also http://mail-index.netbsd.org/port-i386/2011/01/14/msg002247.html

Pull up following revision(s) (requested by joerg in ticket #328):
lib/libc/gen/devname.c: revision 1.22
distrib/sparc64/instfs/dot.profile: revision 1.7
distrib/i386/cdroms/install.sh: revision 1.3
tests/lib/libcurses/director/director.c: revision 1.10
lib/libc/include/reentrant.h: revision 1.15
distrib/amd64/cdroms/install.sh: revision 1.3
tests/include/t_paths.c: revision 1.12
share/man/man7/hier.7: revision 1.101
etc/rc.d/sysdb: revision 1.24
include/stdlib.h: revision 1.99
tests/lib/libcurses/Makefile: revision 1.3
distrib/sparc64/cdroms/installcd/install.sh: revision 1.3
distrib/i386/cdroms/Makefile.cdrom: revision 1.27
lib/libc/gen/ttyname.c: revision 1.25
usr.bin/tic/Makefile: revision 1.2
tools/compat/Makefile: revision 1.57
lib/libterminfo/compile.c: revision 1.7
lib/libc/gen/ttyname.c: revision 1.26
lib/libterminfo/compile.c: revision 1.8
tools/compat/Makefile: revision 1.59
tools/compat/cdbw.h: revision 1.1
distrib/i386/installimage/install.sh: revision 1.2
lib/libc/include/namespace.h: revision 1.154
usr.bin/tic/tic.c: revision 1.13
usr.bin/tic/tic.c: revision 1.14
usr.bin/tic/tic.c: revision 1.15
distrib/sets/lists/base/mi: revision 1.996
usr.bin/tic/tic.c: revision 1.16
usr.sbin/dev_mkdb/dev_mkdb.8: revision 1.13
usr.bin/tic/tic.c: revision 1.17
usr.bin/tic/tic.c: revision 1.18
tools/compat/cdbr.h: revision 1.1
distrib/sparc64/instfs/list: revision 1.25
usr.bin/tic/tic.c: revision 1.19
lib/libc/cdb/cdbw.c: revision 1.4
lib/libc/cdb/cdbw.3: revision 1.4
lib/libc/cdb/cdbw.3: revision 1.5
share/terminfo/Makefile: revision 1.3
usr.sbin/dev_mkdb/dev_mkdb.c: revision 1.29
usr.sbin/dev_mkdb/Makefile: revision 1.8
lib/libc/gen/ttyname.3: revision 1.23
lib/libc/gen/ttyname.3: revision 1.24
lib/libc/cdb/cdbr.c: revision 1.3
include/cdbw.h: revision 1.2
distrib/sparc64/cdroms/installcd/Makefile: revision 1.15
lib/libc/gen/devname.3: revision 1.12
tools/compat/compat_defs.h: revision 1.85
tools/compat/compat_defs.h: revision 1.86
lib/libterminfo/term_private.h: revision 1.10
lib/libterminfo/term.c: revision 1.14
usr.bin/tic/tic.1: revision 1.10
lib/libterminfo/term.c: revision 1.15
lib/libterminfo/Makefile.hash: revision 1.5
lib/libterminfo/term.c: revision 1.16
distrib/amd64/installimage/install.sh: revision 1.2
share/man/man5/rc.conf.5: revision 1.152
distrib/sets/lists/tests/mi: revision 1.472
distrib/amd64/cdroms/Makefile.cdrom: revision 1.7
include/paths.h: revision 1.41
bin/ps/ps.1: revision 1.101
lib/libterminfo/terminfo.5.in: revision 1.16
usr.bin/tic/tic.c: revision 1.20
lib/libterminfo/terminfo.5.in: revision 1.17
Prefer __printflike.
Use queue(3)
Replace linear lookup with hash table, reducing runtime by 60%.
Use e* from util.h.
One more strdup -> estrdup.
Maintain nalias and nterm on the fly.
Add void for ttyslot prototype.
Use memcmp in place of strncmp, since length is known to no longer than
either of the arguments.
Fix a number of memory leaks. Keep final loop of the cleanup in tic(1)
under #ifdef __VALGRIND__ though.
Add __predict_true / __predict_false definitions.
Add a special seeder for cdbw_output that gives stable results.
Hook up cdbw(3) for the tool build.
Prototype for cdbw_stable_seeder.
Provide a usable thr_once for !_REENTRANT
Switch device database to cdb(5). Rework ttyname(3) and ttyname_r(3) to
depend on new devname_r(3) as heart. Add /dev/pts magic directly to
devname(3). While it can lead to returning non-existing paths, the
behavior is more consistent that way. Drop caching layer in devname(3),
it doesn't buy anything for the common case of having access to the
database. Teach devname(3) proper fallback behavior of scanning /dev.
Create both old-style and new-style database for now in /etc/rc.d/sysdb.
Switch terminfo(3) to cdb(5).
Fix typos.
Make Alan Barrett happy and add ().
Add cdbr(3) support to tools/compat.
Bump date for previous.
Relax consistency to make it possible to match valid entries.
Prefix devname's buffer with /dev/ as ttyname is supposed to return the
full path. Reported by Dave Huang.

sync with head