[PVR] PVRManager: Factor out playback state functionality into its own class

[ksooo]

Another PVR refactoring PR. Idea is decoupling and separation of concerns.

In the distant future PVR shall no more know anything about any application playback states. So, this PR is a step into this direction.

Runtime-tested on macOS and Android, latest Kodi master.

[Rechi]

If you prefer the style you used in this PR, crate a PR with documentation and clang-format configuration changes.

[phunkyfish]

Outside of the left align from Rechi it looks good. Not sure if my comments originate from NULL or nullptr so maybe the comment not so important. Up to you.

[ksooo]

If you prefer the style you used in this PR, crate a PR with documentation and clang-format configuration changes.

For the records: I do not accept any clang-format stuff as a blocker for any PR. Team Kodi developers have no common agreement or at least consensus on the rule set you're trying to enforce here by blocking a PR.

I will incorporate all requested changes except the ctor initlist reformat stuff and merge as soon as Jenkins is happy.

[Rechi]

Team Kodi developers have no common agreement or at least consensus on the rule set

That's the reason I'm asking you to submit a PR with your suggestions. Otherwise everyone wants to keep his preferred code style.

[ksooo]

Sigh. Not worth the fight. I have better things to do. I will just obey the existing rules.

[ksooo]

Here we go. All (!) requested changes are in. Please approve or comment on other findings.

code follows now current coding guidelines and clang-format configuration