We have to ensure that languages are installed when module is installed.
It does not matter if that is done immediately or later but it has to be
done. The solution in here is to check if module is installed and if so
also request languages for it.

This adds code that is not pkglists dependent and when any Foris plugin
is installed it should automatically also maintain languages.

Note that lists are not aware of Foris packages existence so they need
list of all existing plugins.

Storage plugin would be now part of three lists. I don't see a reason
why we should not move it to base install instead of installing it on
top of base system. It would be better to have it optional and to have
some dependencies but I think that as it is now it is confusing to user
that storage plugin disappears or appears out of kind of nowhere.

There is no more Install commands for pkglists alone because it is
dependency of updater-ng-supervisor and that is dependency of
foris in proxy. This means that Foris it self pulls pkglists in.

This creates lists that can be included in to each other. This is done
by hack that original script calling one of these lists passes base URI
to access sources and that is later reused. This is how relative URI
should work in future but it is not completed now so we can overcome it
this way and have almost same support.

This also means that we no longer have to specify target branch for
lists because it no longer matters.

Fallback branch is for now dropped because we are not doing small build
at the moment. We should in future return to them but they will be
implemented differently then fallback branch is.

This also does some base list cleanup.