initial rootfs subprofile and services feature

This subprofile is akin to THE_* variables family: the configuration
bits and script hooks sitting there influence whatever chroot is
declared to be the user facing one in the end, whether it comes
from vm image or live subprofile.

The services feature ought to be a changeset of its own which would
be based on rootfs and become the base for ve/vm changes but I chose
to just do it atomically; some pre-existing duplicates are pruned now.
build-{ve,vm}: handle THE_* and DOT_BASE too

Classic VEs don't carry any kernel since these are running
under a single OpenVZ (or potentially LXC) kernel image;
ARM Multiboot (TWRP in this particular case) allows to boot
off a chroot via kexec, and we need a kernel in it for that,
obviously.

No bootloader required inside such VE though.
fonts: generalize (stage2 -> rootfs)

This feature should be more generally applicable indeed.
efi: generalize (stage2 += rootfs)

This feature is more generally applicable indeed;
might result in duplication due to the installer
components adding "efivars" independently but that
is to be sorted out later in those components:
- check whether it's added already sometime soon;
- maybe stop adding that at some point in the future.

install2 and rescue roots still need this too though.
fonts: consistency tweak

The issue is that use/fonts/infinality doesn't actually
require the script hook thus registering the feature's
name in FEATURES variable so that the feature's contents
get copied over is not neccessary (distcfg.mk build-up
will have happened anyways).

But that's confusing if one's forgot this peculiarity
(like me today) or never knew of it, so let's spare
some frustration.
initial init feature

This one is finally there and should help reduce the
systemd-induced mess in package lists and specifications.
initial deflogin feature (security sensitive!)

The feature officially introduces the "engineering passwords"
including empty ones which have been around since forever but
weren't properly managed (and still are not, at least until
there are no stray passwd/chpasswd/usermod calls in both the
profile, installer-features and all the other related parts).

It is based on an m-p-d init3-users script by stanv@ but was
cleaned up and restructured in a pretty severe manner; thanks
glebfm@ for additional discussion.

This also cleans up the kludge previously stuck into build-vm.

Note that vm/icewm sports graphical autologin now as well as
the default root password (which can be overridden by passing
ROOTPW=... to make but it is a change from the previous state
of affairs indeed).
initial armh* features

These handle only VE-like products (think TWRP on Nexus 7);
the proper image support should be backported later on.

An experiment in layered configurations is still in its
early stages regarding ARM zoo...
x11: driver and purpose related refactoring

This has had several goals:
- a target suitable for x86 and armh providing a rather
  minimal set of base xorg packages and generic drivers;
- task-oriented targets for graphics use cases:
  + "desktop" means rather 2D focus with 3D being welcome
    or even essential but not performance critical, thus
    "a slower driver is fine as long as it does work";
  + "3d" means specific 3D performance being critical,
    that is "no 3D means no use at all".

Regarding the free and proprietary 3D-capable drivers:
the previous idea was to split out some common ground
and then add the contenders on top of that; the current
approach is based on the observation that the live images
requiring proprietary NVIDIA/AMD drivers *by default*
are usually of not much use with hardware that lacks
proper 3D acceleration (like Tseng cards) or the driver
support for that (like Matrox these days).

Intel videodriver makes for a special case though:
it is both free and top-notch performer.

Thanks sem@ and boyarsh@ for discussion.

PS: xorg-drv-{keyboard,mouse,void} dropped;
those who need these can usually help themselves.
live: factor out x11-autologin

Hardly belonged there in the first place and became a culprit
during armh branch development since it had to be forked in
an ugly manner; move to rootfs hooks and be done with it.

VM images will be able to benefit either *but* installed systems
might have some trouble when this is implemented:
http://lists.altlinux.org/pipermail/devel/2013-May/197447.html

Split off use/live/x11 as a common free/proprietary ground either
(this refactoring had to be performed in parallel with x11 feature
being revamped, diffs quickly became intertangled unfortunately).
x11-autologin: factor out x11-autostart

It has value of its own and can be used standalone;
autologin does require autostart though.

Adjust x11 feature targets accordingly.
live.mk, test.mk: drop obsolete targets

live-{gnome,cinnamon,mate,sugar} have been superseded by regular-*
(see regular.mk); live-mate-systemd has no sense now either.
live: disable dmeventd by default too

A service a day makes the boot a long wait!
pkg/lists: tweak Makefile to expand variables

The issue at hand is the hack to be employed in the init feature:

	@$(call add,THE_LISTS,$$(INIT_TYPE))

where INIT_TYPE is set separately; $(value $V) would leave that kind
of substitution unmolested while we would actually need it done.
metadata: fix a tiny bitrot

The generated comment went wrong when the script was renamed.
stage1: add ehci_marvell to modules

This is ARM-specific (more specifically, Marvell ArmadaXP-specific
for me right now) but doesn't hurt if the module is absent.
tar2vm: rewrote as tar2fs

Overview of the changes:
- ARM support: separate ext2 /boot, no LILO
- avoid race condition with devmapper
- trap ERR so that -e in shebang doesn't result in extra cleanup hassle
- configurable root filesystem type (ext4 by default)
- jumps through parted hoops

Details:

1. LILO is x86-specific while the rest of the script can be used
   to prepare e.g. Marvell ArmadaXP or CuBox images; we can generally
   count on uboot supporting ext2 for relatively sane platforms but
   not ext4 that would be a better root filesystem performance-wise.

2. Apparently /dev/mapper/loopXpY can be still missing at the time
   when kpartx returns and pop up a bit later... sit there, wait
   and check for it.

3. If something went wrong with any command of the script it would bail out
   due to -e in shebang; it is now better to clean up the loopback device
   and its mappings in this situation either.

4. One size doesn't fit all, really.

5. The parted sizing was sloppy as in broken, now it's just half insane.
   Someone's decision to stick units and auto-alignment knobs into
   a single one was apparently hilarious...

   http://www.gnu.org/software/parted/manual/parted.html#unit

Manual loop/dm cleanup is described in documentation just in case.

/boot size meter is suboptimal in terms of additional I/O incurred,
will be most likely rewritten to make use of advance "du -s".
slinux/misc: drop an obsolete package

gdm-theme-simply is still around but turns out that it counts
on gdm2.20 (providing gdm) to be installed, and it is not;
thus gdm-3 is actually pulled in and it doesn't work here.

The package should be dropped from Sisyphus probably,
let's drop it here anyways.
x11: added use/x11/mate target

It was implemented in a pretty quick-and-dirty way
for regular-mate back then, clean things up a bit.
Package lists should be deduplicated either but
that's another story.
armh: added umkimage support

It was actually done much earlier during an experiment with
Marvell ArmadaXP but is now integrated more or less properly.

NB: ext2 is not needed anymore (uboot should do it),
ext4 should become configurable by an existing knob.