REF: added possibility to crop or not around landmarks during straightening
REF: added possibility to crop or not around landmarks during straightening

Former-commit-id: cd86db6af10f88eb59fac60c1dd21293d6919d23
Former-commit-id: d16b0d2b33806bd0e90f0c5311c2df3000a3125d
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox