As recently discussed with Jack Kim [X] and Gregory O'neill [X], update the TOC views to match the latest mockups.

https://www.figma.com/file/VJuFJNGaVSwdXF2VWiVuZ4oe/NYPL-SimplyE-mobile?node-id=159%3A0

For the Android implementation:

1. Remove the text from the circular progress indicators, and use a grey background for the ring (so that a grey ring indicates 0% progress).
2. Add an icon when there's an error.
3. Remove the ability to delete individual parts.
4. Add a small "refresh" icon used to download parts.
5. Add a "refresh all" option in the action bar that triggers a download of all parts and dismisses any existing errors