- adds graph of sunlight over the year, and time of earliest/latest sunrise/sunset.
- adds support for customizing map and graph colors.
- adds support for custom events based on "shadow length".
- adds "bedtime mode" to alarms; helps schedule do-not-disturb during sleep hours.
- adds "use app location" option to alarms; reschedules alarms when the location changes.
- adds "high brightness" option to alarms, and "swipe to dismiss" alarm UI.
- adds "next alarm" quick settings tile, and "next alarm" widgets.
- fixes bug "alarms fail to display over lock screen" (#802).
- updates targetSdkVersion from 25 to 28 (Android 9); adds support for notification channels.