Add an exclude list to the template file.

When selecting directories to delete, reverse-sort so rmdir
will work.
Don't put the packages into _.instufs -- that only slows down
the installer boot time.  Significantly.
Change the default conf file.
Some fairly major changes.  Not complete yet -- not sure how
it's going to handle delta packages, really.  But it's getting
there.
Some fairly major changes to how build is done.

This makes a release into three packages.
A whole slew of more changes, related to getting it to build.
And install.  And upgrade from ISO.