REF: moved isct_test_function into script (don't forget to run create_links)
REF: moved isct_test_function into script (don't forget to run create_links)

Former-commit-id: f4be9be9d6bcf5a0a7c7c76a6bb5b2969b0b4924
Former-commit-id: 3716e4ca7fb0cfb02f42179157c710987dd07874
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox