Bring back `--bluray-angle` feature

[comfyneet]

Some Blu-ray discs contain scenes that can be viewed from multiple angles. This option tells mpv which angle to use (default: 1):

--bluray-angle=<ID>

mpv used to support this feature, but it was accidentally dropped when removing dvd/bluray menu support in 2 commits: c844d57 and 35e8b6c.

[ESSEMDEE]

I ditto this request. I glanced at the code, but it was beyond my abilities to even find where the change would need to be made.

But having to manually edit MPLS files to access a desired angle is highly inconvenient. (And if one is playing direct from the disc — and not a ripped backup — said editing is not even possible.)