Android: Reusable sample app

[katie1006]

Is your feature request related to a problem? Please describe.

When I write custom assets for my own project, there's no easy way to test them locally with sample Player content. What I end up doing often is copy-pasting almost the entire sample app module from the Player Android project, since the sample app is well put together. This is not a hard task, but it is tedious.

Describe the solution you'd like

It would be nice if the sample app can be extended in some way. Ideally, it should be flexible for

• small and simple projects where I can plug in the sample app, throw some Player content in the assets folder, and see how they render
• bigger projects where I can extend the sample app, customize it with additional asset functionalities to be demoed (like theme switching)
• complex projects where Player is only one of the capabilities/screens to be demoed in the app

Additional context