sysutils/rinse: update to 3.1.1

While here fix license confusion. debian/copyright states it's one of
the "common" licenses but our ARTPERL10 isn't such because unlike ART10
it lacks a copy under Templates/Licenses/.

ChangeLog:

• fedora-2*: add findutils, iputils
• fedora-22: add packages for dnf plugins
• fedora-22/post-install.sh: better DNF support