Add 45x35 portrait aspect ratio to crop module

[da-phil]

Add the popular 45x35 aspect ratio to the crop module.
This aspect ratio is also used for IDs and passports.

[da-phil]

Can anybody shed some light on how to update the PO files to add this new translatable string? Maybe @ralfbrown or @TurboGit?
Which also brings me to the related question if this how-to is still up-to-date: https://github.com/darktable-org/darktable/blob/master/doc/TRANSLATORS.md

[ralfbrown]

What you did is exactly what is needed - after merging into master, the next time the translation files are updated, the new string inside _("") will be added to the PO files and the translators can then translate it.