Material 3.0 updates

[UweTrottmann]

Follow-ups from #884.

• Draw behind system bars in MovieDetailsActivity.
• Comments: use round images.
• Use cards to separate panes on wide layouts. https://developer.android.com/large-screens/gallery/productivity
  • Episodes
  • People
• Snackbars not moved if button bar navigation is shown (obvious, since they adjust to the attached parent, which draws behind).
• Update snackbar in ShowsActivityImpl does adjust for navigation bar, but it shouldn't.
  • This is similar to [Snackbar] Snackbar bottom margin is incorrect when using window insets with padding material-components/material-components-android#3446 (but that uses an anchor view, where it's odd that it still applies the extra margin). Commented there.

[UweTrottmann]

Snackbars:

• Removing the window inset listener kind of works ViewCompat.setOnApplyWindowInsetsListener(snackbar.view, null), however the layout has large top and bottom padding then?!
• Forcefully setting bottom margin to 0 does not work as the insets seem to be applied later.