bin/mktmpdir: hasher might be unconfigured yet

No need to just go ahead and source files in potentially
unavailable directories, really.
Makefile: drop extra >&2

say() redirects to stderr already.
conf.d/README: updated reference

Argh, is it overdocumentation already?
The temporary name bites once again...
build-vm: standalone build is a must, too

The problem was spotted by Alexander Bandura:
bin/tar2vm wasn't present in the generated profile.

I considered extending features.in/Makefile to include
bin/ alongside lib/ but that would make the helper's location
unpredictable (unless BUILDDIR is specified explicitly) so
restricting sudoers would be harder; worse yet, the copied file
would come with write access for the user building an image.

The implications in restricted case are complex enough anyways
so the recommended implementation would only include a fixed
readonly location like /usr/share/mkimage-profiles/bin/tar2vm
as laid out in doc/vm.txt, and that means it's in the metaprofile
not a generated profile.
live, rescue: fix stage2cfg.mk LISTS/PACKAGES order

The reason is that package lists and individual packages
are processed in different dependency resolution "transactions"
by mkimage; thus if packages (the more precise form of specifying
the contents) come first they can't override the lists appearing
later, and that's wrong: we should be able to specify the more
generic things and then pinpoint the specifics.

This became apparent while authoring [[Mkimage/Profiles/m-p/howto]]
asked for by drool@.
x11: ensure kdm3 installation for tde

TDE distros don't really need kdm4 which was proposed as
a replacement by zerg@ (for all the valid reasons but kdm3
wasn't maintained at that point, this has changed since).
lib/ve.mk: whoops, ve/bare misses /sbin/init

Actually the templates pretending to be usable missed the whole
interactivesystem (sysvinit would get pulled in by services as well).

Fixed somewhat but time and practice will tell.
conf.d/live.mk: ugly thinko fix, thx enp@

"textinst" != "textinstall", so let's just stick to the latter form.
initial live-testserver.iso

Also pulled the pkglist/kmodule part out of distro/server-mini's
recipe and started off a standalone feature based on it.

NB: el-smp kernel now contains aufs as a module but propagator
doesn't try to modprobe it.
Makefile: fix default target to provide help again

`help' used to be the default target described at the very top
of the toplevel makefile but that got broken with g2f307ff;
spotted while discussing m-p with enp@.
branding: clarify README

It wasn't obvious at all what BRANDING variable is for
(at least until the source code and existing configurarion
has been examined).
server-nano += +power

Essentially all the relevant server images got cpufreq setup
and a power button handler; feel free to ask for revert if
this causes any harm in any situation.
lib/clean.mk: post-build cleanup revisited

The prerequisites for a cleanup after a successful build
were somewhat weird at this point; now the rules are:
- if DEBUG level is more than 1 or CHECK is set, don't do it;
- otherwise if at least one of the following conditions is true:
  + there's more than one target being built in a row;
  + the build was run by e.g. alterator-mkimage;
  + metaprofile directory is read only
  ...then do a distclean.

If these are still weird or feel unsuitable for profile hacking,
drop me a note (or a patch).
0.7.5-alt1

- a bunch of fixups and cleanups
gear-store-tags