Features: * #3267875 by DamienMcKenna: Pseudo/extra field for displaying EXIF data on media edit forms. Bug fixes: * #3561883 by damienmckenna: ExifPHPExtension::readMetadataTags() assumes data is arrays. * #3566083 by damienmckenna: Undefined variable $extra exif.module. * #3567458 by damienmckenna: Add Media form fails with error. Tasks: * #3564769 by DamienMcKenna: Verify tests work.