NEW: test for -concat and -split options in sct_image
NEW: test for -concat and -split options in sct_image

Former-commit-id: 2478653c96222ef47aabef692b1b162fc12fb0c3 [formerly 5f9b0dc0e4d10a9c8680d59a3c16ea48c5e51e2b]
Former-commit-id: 26b06ac631a4d74dce7cbfc9491328bc8aa8181b
Former-commit-id: 6caa3df7980973aac8e0f731d84e1d328ba10da5
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox