directory with currently installed packages.
This script will delete any ${DISTFILE} in ${DISTDIR} that does not currently
have an installed package as an owner.
If you play with packages a fair bit and download some just to have a play with
and delete the package later your ${DISTDIR} can end up with a lot of orphaned
${DISTFILES}. While lintpkgsrc will help you remove outdated ${DISTFILES} it
does not do any corealtion with installed packakges which is the gap this
script aims to fill.
With "lintpkgsrc -or && pkg_distinst --delete" you can and up with a fairly
lean and current ${DISTDIR}.
