add(profiles): Add profiles.desc to identify valid profiles
fix(profiles): Drop references to virtual/portage

The old-style virtual/portage is gone and replaced by a new-style
virtual/package-manager in Gentoo. For now just use sys-apps/portage
since that's all we want anyway.
fix(profiles): Add 'threads' to the bootstrap use flags

This works around a dependency issue caused by our newer portage ebuilds
depending on +threads in our older python ebuilds. Will go away later.
fix(profiles): Add 'curl' to bootstrap use flags.

We are still using the Google toolchain which is in git, so add curl
support the bootstrapped git package so it can fetch the toolchain.
add(sys-apps/efunctions): Replace coreos-base version with generic one.

This version of efunctions does not depend on cros workon and git to
install and thus is suitable for bootstrapping. It also uses the
original author as the upstream rather than a coreos mirror. Since it is
not coreos specific any more I've moved it to sys-apps.

Added to both system and bootstrap package sets.

For extra fun it is also in my new systemd-only Gentoo overlay:
https://github.com/marineam/systemd-only-overlay
fix(profiles): Move USE from make.conf to make.defaults in profiles.

Moving more things into the profiles means we eventually reduce the
magic around generating make.conf and aids bootstrapping.
fix(profiles): Add shadow to the bootstrap package list

Despite the big scary warning saying otherwise upstream Gentoo has
actually included shadow in this list since 2011 (while also forgetting
to delete the warning, cute!). Not having it here runs the risk of
causing a failure during catalyst builds if something tries to add a
system user or group before shadow gets installed.

Upstream commit:
http://sources.gentoo.org/cgi-bin/viewvc.cgi/gentoo-x86/profiles/default/linux/packages.build?r1=1.5&r2=1.6
fix(profiles): Don't use live ebuilds by default.

As-is catalyst and cros-workon's live ebuilds don't mix since the
catalyst chroot does not provide /mnt/host like the sdk chroot does.
Besides, only people actively working on a project should use the live
versions since anyone else will install it one time and then never
upgrade after that, even when the version marked stable is actually
newer than their old live build.

For SDK builds this means not accepting ~amd64 for core-admin and
update_engine and adding a stable ebuild for core-admin. (update_engine
already has a stable ebuild which is even up-to-date)
fix(coreos-base/update_engine): Add missing dependency to stable ebuild.

This fix previously made it into the live ebuild but not the stable one.
fix(coreos/config): Replace old ChromiumOS SDK binhosts and tarball.

Building our own packages so we don't want the old ones! This is just a
first stage, automated builds aren't going yet and I'm not covering
amd64-generic and its cross toolchain, just the sdk.

The old binhost/host/*.conf files are just stubbed out until I'm
positive nothing else is referring to them.
fix(coreos/config): Switch download host to our own CNAME

We now have http://storage.core-os.net/ working so use that instead of
the generic Google host name.
Merge pull request #25 from marineam/bootstrap

Bootstrap