Add option to play mp4 videos to save battery and screen on and add a sleep time

[trimechee]

Hello, Dopamine is great and amazing, thank you very much ! Please I have an important request : when i sleep, I put tv shows and i download entertainment and humor tv shows in mp4 format and i like to listen to them when i sleep so I used dopamine to only play back the audio from these videos so the screen of my computer remained off but Dopamine can not playback the audio of mp4 video unfortunately, it will be wonderful if Dopamine adds this possibility and also add a "sleep timer" to program the shutdown of the computer, thank you very much !