- Adjusts how we remove pacakges. Gentoo maintains a list of packages
that the user has requested be installed called "world". By
deselecting the packages, we remove them from this list, and at the
end, call depclean which will uninstall packages no longer selected or
needed as dependencies.
- Updates profile logic. We should theoretically be able to support any
new gentoo profile, without having to maintain a static list ourself
by just updating the base.
- Updates CI job to use default profile as determined by the gentoo
element. This basically eliminates one more place we need to update
profiles on change.
- Ensures we install installkernel with USE=+grub so we actually install
the kernel
- Do not use testing (~amd64) packages unless absolutely neccessary
- Fix growroot openrc initscript to use /sbin/openrc-run instead of
deprecated-and-now-removed /sbin/runscript.
Change-Id: Ie9d2ab67d72114603034374854bb3a3d52de8ca4
f831b3d0b6