feat(profiles): shuffle around some excludes for dev images

Dev images need to be a full build environment but still don't need
extra things like gtk-docs or extra config files. Adjust accordingly.
feat(profiles): Set proper mask in dev and prod sub-profiles.
Merge pull request #686 from marineam/systemd

Revert back to systemd 212
Merge pull request #683 from marineam/profiles

Setup new image profiles
fix(coreos-base/oem-vagrant): Update minimum version to 1.6.0

Commits 24cdca8e and 9d2c0169 added options only in 1.6 and later,
breaking compatibility with older versions. Update the minimum version
to make the resulting error more obvious. :)

The coreos-vagrant project already required 1.6 (although not
explicitly, probably should fix that) so most uses probably won't notice.
Merge pull request #688 from marineam/vagrant

fix(oreos-base/oem-vagrant): Update minimum version to 1.6.0
feat(sys-apps/systemd): netdev - allow setting MACAddress in .netdev

Pull in 96c907 from freedesktop.org/systemd/systemd.git for v212
Merge pull request #687 from crawford/networkd

feat(sys-apps/systemd): netdev - allow setting MACAddress in .netdev files
bump(sys-kernel/coreos-kernel): bump to 3.15.1 release
Merge pull request #689 from gregkh/kernel_update

bump(sys-kernel/coreos-kernel): bump to 3.15.1 release
bump(sys-kernel/coreos-firmware): Update to new snapshot

This includes new bnx2x firmware required by linux 3.15:
 * Missing firmware: bnx2x/bnx2x-e2-7.8.19.0.fw (bnx2x.ko)
 * Missing firmware: bnx2x/bnx2x-e1h-7.8.19.0.fw (bnx2x.ko)
 * Missing firmware: bnx2x/bnx2x-e1-7.8.19.0.fw (bnx2x.ko)
Merge pull request #690 from marineam/firmware

bump(sys-kernel/coreos-firmware): Update to new snapshot
bump(coreos-base/coreos-cloudinit): bugfix release 0.7.7

Fixes unit issues that caused configdrive to be ignored.
Merge pull request #691 from marineam/mount

bump(coreos-base/coreos-cloudinit): bugfix release 0.7.7
chore(metadata): Regenerate cache
bump(app-admin/locksmith): v0.1.4
Merge pull request #692 from jonboulle/master

bump(app-admin/locksmith): v0.1.4
fix(sys-apps/systemd): Disable elfutils dependency

Recently added to systemd, configure is detecting elfutils as present
but compilation fails, perhaps a version mismatch. Need to report this
to Gentoo so they can add a proper use flag and dependency.