Know if recorder is running

[floriangbh]

Hello,

Since https://github.com/shogo4405/HaishinKit.swift/pull/1319/files we are not unable to check if the mixer.recorder.isRunning.

Is there any other way to check if the stream is running ?

Use case : handling network cuts and different recording settings

Thanks

[shogo4405]

Certainly, it is necessary. I added the NetStream#isRecording property. b223002

[floriangbh]

Thanks !