• Use 'squeezelite-mobile' as 'Model' reported to LMS if on cellular or metered network. This is to be consistent with LyrPlay and xPlay.
• Increase minimum Android version to 9.0
• Add option to control stopping of player when powered off.
• Fix handling of media keys.
• Add option to delay start on boot by 5, 10, 20, or 30 seconds.
