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

Explicitly exit with success

MFC after: 3 days
X-MFC-to: stable/10

Give a brief message as to what error was encountered to help the user along.

Reviewed by: nwhitehorn
MFC after: 2 weeks

A series of changes tested together as a whole:
+ Add a `-D FILE" command-line option for overriding the path to the
bsdinstall log file (BSDINSTALL_LOG env var).
+ Document new `-D FILE' in the man page for bsdinstall.
+ If FILE in `-D FILE' begins with a +, debug output goes to stdout
(interleaved between dialog(1) invocations/output) as well as to FILE
(minus the leading + of course).
+ If BSDINSTALL_LOG cannot be written, then debugging is disabled (except in
the case of a leading + in the pathname, wherein debug will still be
printed to stdout).
+ Update source code formatting style.
+ Fix a dangling participle ("Begun ..." -> "Began ...")
+ Rewrite the docsinstall script (was necessary to abate direct dependency
on BSDINSTALL_LOG (instead, use fault-tolerant bsdconfig framework which
displays appropriate errors for package management).
NB: docsinstall is still using pkg(8) after this change.
+ Add additional debug output for dhclient/rtsol/wpa_cliscan
+ Display script errors in a textbox rather than just on stdout
+ Update many coments.
+ Add new f_show_err() API call (like f_show_msg but changes the dialog
title to "Error")(see bsdconfig's `common.subr').
+ Add new f_eval_catch() API call for executing a command via eval but not
before logging the command to debug. Several example cases documented in
API header for function in bsdconfig's `common.subr'.
+ Fix dialog auto-sizing when launched as an rvalue to a pipe for indirected
scripts (previously would default to 24x80 sizing in this case, now it can
autosize to full size even when in a pipe chain).
+ Fix bug in f_snprintf if $format argument began with "-"; printf would
misinterpret as a flag. (this is in bsdcofig's `strings.subr').
+ Add accompanying f_sprintf() and f_vsprintf() to go along with already
existing f_snprintf() and f_vsnprintf() (see bsdconfig's `strings.subr').
+ Remove some unnecessary default ZFS datasets from the automatic "zfsboot"
script. Such as: /usr/ports/distfiles /usr/ports/packages /usr/obj /var/db
/var/empty /var/mail and /var/run (these can all be created as-needed once
the system is installed).
+ Remove setuid=off for /usr/home (as discussed from last round of CFT).
+ Fix some i18n string violations in "zfsboot".
+ Bolster debugging output in "zfsboot".
+ Fix some string quoting issues in "zfsboot".
+ Fix some variable scope issues in "zfsboot".
+ Change "Create" to "Install" in "zfsboot" main menu.
+ Increase error checking in "zfsboot" (type-check arguments and such).
+ Add call to "graid destroy" killing automatic metadata (part of the series
of pedantic destructions we do when bootstrapping a new/naked disk).
+ Make judicious use of new f_eval_catch() in "zfsboot".
+ Fixup some variable names for consistency (zfsboot).
+ Fix an underride syntax parameter expansion folly (zfsboot).
+ Confirm layout if not explicitly chosen when blindly proceeding (no
longer have to touch anything on the ZFS menu if it scares you, just
choose the omnibus "Install" option at the top and you'll be prompted to
select vdev type and disks in the layout confirmation dialog).
+ Change numbered menu items to alphabetic for more efficient navigation.
+ Consolidate vdev selection and disk selection into a single stateful
menu which performs validation and allows backing out to each previous
menu as you go deeper.
+ Redesign the ``Last Chance'' dialog (still using the same colors, but
make it conform to a tolerable width and make disks appear in a block-
quote style indented region).
+ Fix a bug wherein we used the a lowercase variable name by accident
(actual variable name declared as all-uppercase) at the time of
initializing fstab(5) (not believed to cause any issues though).
+ Update the geli setup infobox for each provider being initialized
(not just at the onset -- since each ``geli init'' causes kernel messages
to push our infobox off-screen).

Reviewed by: Allan Jude <freebsd@allanjude.com>
Discussed on: -current
MFC after: 3 days

After installation, dump 4096 bytes from /dev/random to /entropy in the
newly installed system. This should greatly increase the amount of
entropy available when SSH host keys are generated during first boot.

Reviewed by: markm, nathanw
Approved by: re (gjb)

Fix mirror selection, which was broken by stderr redirection.

Reported by: Garrett Cooper

Update to reflect net install changes.

Add support for optional distributions, installation of the ports tree and
src. Fitting all of this on a single CD along with a full system requires
changing the default compression algorithm from gzip to xz.

Import bsdinstall. This is meant to be (eventually in conjunction with
pc-sysinstall) a replacement for sysinstall in the 9.0 release and beyond.
Currently supported platforms are sparc64, pc98, i386, amd64, powerpc, and
powerpc64. Integration into the build system will occur in the coming
weeks.

Merging with pc-sysinstall will use this code as a frontend, while
temporarily retaining the interactive partition editor here. This work
will be done in parallel with improvements on this code and release
integration.

Thanks to all who have provided testing and comments!