Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Create /tmp/bsdinstall_etc even if we aren't starting the installer so that
dhclient can write resolv.conf when used from the live environment.

PR: 176078
MFC after: 3 days

Move the installer's keymap solution introduced by SVN r259468. The new
location of /etc/rc.local on the install media is more appropriate as it
knows serial vs. non-serial and can also do the change earlier (so that
even the initial Install dialog can benefit from the change).

MFC after: 3 days

Fix typo and simplify condition.

Submitted by: Christoph Mallon <christoph dot mallon at gmx dot de>

More automated install support: if a script exists at /etc/installerconfig,
point the installer there and then reboot without asking questions. This
design subject to future change.

- Set TERM to cons25w on pc98 because we still use old cons25w terminal
to show Japanese.
- Add cons25w to terminal lists.

Reviewed by: nwhitehorn
MFC after: 1 week

Fix installation script after r230482 -- a missing character apparently.
Now, back to convalescing.

Part of r230482 didn't actually work. Revert it for now. This means PR
161047 isn't actually fixed.

PR: bin/161047

Do a test in a better way. Editing files after testing them is never wise.

Per popular demand, if installing from a graphics terminal, run the
installer on a VTY with no kernel messages (VTY 2), show the installer
log in real time on VTY 3, and spawn a shell on VTY 4.

PR: bin/161047, bin/161048
MFC after: 2 weeks

Inquire about terminal type if starting from a serial console and do
not configure the host's networking if netbooted [1]. Also fix FTP
installations behind some firewalls [2].

PR: bin/159583 [2]
Reported by: stas [1]
Approved by: re (kib)

Allow the user to use the live environment post-installation, as well
as improving error handling.

Add additional release makefile for bsdinstall-based media, along with
support files. This does not change the default behavior of anything.

To make bsdinstall-based media, pre-build world and GENERIC, then run
the release target in Makefile.bsdinstall.