Support for Dark Mode in iOS 13.
Various usability improvements.

Support for iOS 11.
Support for iPhone X.

- Updated for iOS 8
- Progress indicators now contain more visual detail. Light shading used to indicate standards have been started.  Dark shading used to indicate standards have been completed.

- Updated for iOS 7.
- Now track progress for each standard individually.
- Mark progress as incomplete, in-progress (started) and complete.
- Content updates.