Allow durations for the controls hide timer

[doppio]

Chewie waits 3 seconds after user interactions before hiding the controls. For my use case with a short video, 3 seconds feels way too long. I plan to fork Chewie to implement a new parameter for the duration. Would you accept a pull request for this feature?

[diegotori]

@doppio Yes, we definitely take PRs for this. Feel free to submit when you're ready and myself or maherjaafar will review your proposed changes.