fix satellite subscription handling

[PeterMocary]

As a followup on PR #348, fix the satellite subscription problem which originates from use of handlers and include_role incompatibility. Since using include_role is not supported in handlers (ansible/ansible#20493), it is not a good idea to wrap it in include_tasks and use it anyways. Thus, this patch removes the handlers entirely and converts them into regular tasks. This solution is inline with the original idea (#348 (comment)) and basically similar to the key handling in the upgrade role.

Not tested yet, although I'm already able to setup satellite host and upgrade it. I'll try it soon.

[richm]

[citest]

[PeterMocary]

Changed the when statements so that they handle null in variables. Defined these to empty string, however, that could be changed back to null if not desired. In my opinion having empty string as default is better.

[PeterMocary]

[citest]

[PeterMocary]

[citest]

[PeterMocary]

[citest]

[PeterMocary]

[citest]

[PeterMocary]

I tried upgrading 8to9 with multiple different activation keys (pre_leapp, post_leapp and regular leapp AK) with different repositories exposed. It worked fine and reregistered every time resulting in a system subscribed with post_leapp key.

[richm]

Ready to merge?

[PeterMocary]

[citest]

[PeterMocary]

I've made the pre and post activation keys mirror the upgrade key if not specified. This makes them optional.

Tested on 8to9 satellite upgrade with multiple keys and single key. Both worked fine.

[PeterMocary]

Fixed duplicated readme section and added changelog note about the activation key variables change.

[PeterMocary]

[citest]