[Feature request] Add a way to start playing a playlist from homescreen

[brunetton]

Checklist

• I have tested the latest 5.0 beta version, and it doesn't have this feature.
• I have searched for existing issues (open and closed) and confirmed this feature hasn't been requested before
• I believe this feature request will benefit more than 10% of users, not just myself

Feature Description

I really love PipePipe (and thank you very much for this amazing software !)
The main thing I miss (in fact my mother miss) is a "way" to start playing a playlist from home screen, like a widget, or (better ?) an exposed activity.

The user experience would be:

• I click on the icon representing the playlist on my launcher
• PipePipe starts playing this playlist in the background

This replaces:

• I open PipePipe
• I go to playlists panel
• I open the playlist I like
• I click on "play in background"

Hope this is clear. Thank you again !