Mostly a maintenance update. Changes include:
- Fix layout display of wide photo layouts in print and upload preview.
- Warn of low disk space if save folder drops below 10 MB of free space.
- Add help links to some settings
- Update sequence to save, print, prompt, upload, and then preview. As a result of this simplification, the "Show Preview At" setting has been removed.
- Backup single photo to sparkbooth-photo folder if current save folder is unavailable