Fixed #11888 - Changed providers to use osfamily fact.

Previously the up2date, redhat and systemd providers used the
operatingsystem fact to select defaults and constraints. This often
meant that new operating systems using the same providers had to be
manually added to the list of supported operating systems

This commit replaces the use of operatingsystem with osfamily meaning
addition of new operating systems is now centralised in one place in
Facter rather than requiring multiple updates.

Tests supporting this have been added to prevent regressions.