This refreshes the albums thumbnails', checking that each image in the album has a corresponding thumbnail and medium sized image.
It leaves any existing thumbnail and medium images alone, just creating any which are missing.
This also refreshes the albums thumbnails', checking that each image in the album has a corresponding thumbnail and medium sized image.
However, it recreates all of the thumbnail and medium images, overwriting any which already exist.
Set file dates and times to picture exif dates and times.
