[Katello] Website and Documentation Updates


As part of our 2.1 release, we wanted to version our documentation such
that users running older versions could still find relevant information. I
am happy to announce that http.//www.katello.org is now versioned with 2.0,
2.1 and nightly docs available from the now Documentation dropdown.

For reference, the docs are generated from each release brand of katello.org
using this deploy script -
https://github.com/Katello/katello.org/tree/deploy . Further, the website
is now auto-generated on every merge request to the repository within the
CI system. See