Add support for public chat

[salirzv]

Hi everyone
once again thank you for developing this amazing software

I was wondering if there was an option to dedicate a part of the output video to the chat (like the options for deskshare and webcam and presentation, we could have a complete all in one solution for sharing the recorded session with out the need to have a host for playback (right now if we want to have chat included we have to use the play back page, which is restricting if we wanted to use some sort of external space)

thanks for your time