WIP: Rewrite the app user interface using Jetpack Compose

[damontecres]

This is a work in progress!

This is the beginning of a complete rewrite of the user interface using Jetpack Compose. "Jetpack Compose is Android’s recommended modern toolkit for building native UI." The current implementation using the Leanback UI toolkit is "discouraged".

This PR is not at all complete and large portions of the app do not work. Additionally, the theming and colors haven't been implemented.

Rationale

Switching to Compose brings some great advantages:

1. Speed! Rendering the screens of the app is significantly faster!
2. A navigation drawer
   • Allows for moving between data types without having to go all the way back to the home page
3. Bypasses having to fix some problems such as Fragments do not follow correct practices #328
4. Built-in UI components for "Immersive Lists" and "Featured carousels" (https://developer.android.com/design/ui/tv/guides/components)
   • These features are now ubiquitous in TV apps

Tasks

• Home page
• WIP: Scene details
  • Convert playback to compose?
• Movie/Group details
• Marker details
• Performer details
• Studio details
• WIP: Tag details
• Image details
  • Scroll between images
• Gallery details
• Filter page
  • Switch saved filters
  • Change sort by
• Search page
• Settings page?
• Theme
• ???

Sample screenshot

This is just a sample without any theming.