Add images iteration 9 tests

*Added get_image_after_successful_import test
*Added get_images_using_additional_property_filter test
*Added get_images_using_owner_sort_key test
*Replaced unittest2 with unittest
*Updated copyright date

Change-Id: I064d74f18e6a5d87ba86dd334b8432909c6f54e5
Merge "Add images iteration 9 tests"