Ensure we become root before installing package, and add a Vagrant test as the…

See merge request !4

Ensure we become root before installing package, and add a Vagrant test as the docker test didn't catch that

Enable use of role on CentOS 7

See merge request !3

* Remove duplicated code.
* Clean up conditionals.
* Shorten fail message.

Get the CI running.

See merge request !1

[ci skip] Make fact gathering explicit.

See merge request !2

If you disable that (and people do for faster runs), then you won't be
able to get the basic facts that are built in (like distribution
version). So, better just put this here to be clear about that.