Added support for OracleLinux Distro:

  * added support for OracleLinux to params.pp

I see that changing the facter value lookup from ::operatingsystem to
::osfamily but the values for darwin and freebsd don't
appear to be included in current facter code:
https://github.com/puppetlabs/facter/blob/master/lib/facter/osfamily.rb