Blender Git Commit Log

- re-wrote image exporting function renaming it from BKE_export_image to BKE_get_image_export_path because now it doesn't copy
files but only manipulates paths. It produces both ablsolute and relative paths. COLLADA exporter can now use it.
- re-wrote unit test for it, this is now more compact and readable
- RNA API Image.get_export_path takes a boolean arg to indicate whether a relative or absolute path should be returned. Python scripts
can now use it.