[evol] added more links from artwork steps to the artwork
[cosmetic] added position number to artwork_step_images, only visible in the admin pages, to be able to change order for steps made the same day (closes #16)
[evol] don't crash when no EXIF data are found
[fix] remove hardcoded submit label in display_standard_form_buttons() helper and propagate submit_label view variable to it
[fix] don't call the final artwork image a 'step', and use italic characters
[lang] updated french translation and french application title
Initial version