TEST: updated .travis.yml: put create_links AFTER declaring SCT_DIR
TEST: updated .travis.yml: put create_links AFTER declaring SCT_DIR

Former-commit-id: 57db2320d4dc9d6b152a0541822c90af42b5cd99
Former-commit-id: c78d50e01f9ccfd6b6b25f3d11826b70bcef5d82
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox