Add hiera support for Oracle Linux 8

[bschonec]

./data/os/OracleLinux/8.yaml needs to be created. I copied 7.yaml to 8.yaml and tested it successfully against all of my Oracle Linux 8 servers.

[demonstrator]

I think this module has been abandoned I'm afraid.

[bschonec]

That's unfortunate as ghoneycutt has been a big contributor to the Puppet world. Do you have any recommendations for an alternative module for SSH management?

[Phil-Friderici]

Support for Oracle Linux 8 will be added with PR #398.

[ghoneycutt]

Thank you for your contributions and help! This is merged in #402 and released in 4.1.0.