- replaced BKE_copy_images with BKE_export_image, now it handles only one image at a time, this is better since for exporters it is easier to export one image at a time writing new image path to a file - exposing BKE_export_image in RNA as Image.export, interestingly, RNA allowed me to define a function with PROP_STRING return type although it doesn't free memory, will fix that in the next commit - removed bpy.util.copy_images Unit tests: - re-wrote a test for BKE_export_image, it's more compact now - moved unit tests to the creator module to avoid another executable, now running tests with `blender --test` - as before, unit tests are built only if WITH_BF_UNIT_TEST is non 0