DEV: sct_template_crop_data: new function to crop preprocessed data
DEV: sct_template_crop_data: new function to crop preprocessed data

Former-commit-id: d4b78a55c2ea5909595aff8fe1e7cfbe02212d2c [formerly 79945fcd55a1895d4cff4f101b4822c184e786ca]
Former-commit-id: 98f66e8006493073d800d9e221ee3f61526ec6c3
Former-commit-id: 8fb81067a330ca7d28fb041e1980b0f9a74db56b
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox