playback of AV1 with HDR and DoVi

[MagicDoubleM 121]

It's now possible to encode av1 with HDR and even include DoVi through SVT-AV1-PSY.

Playback of these files surely depends on clients hardware, and the state of the vendors exoplayer libs, that is known. But currently only the AndroidTV client allows playback at all, by triggering the server to reencode. With the Android-Client things stay dark and playback never starts. I'm testing on a few FireTV devices, including the latest cube and 4k max stick.

[ebr 16169]

I would consider this a bug.  Moving to Android.