BUG: fixed #232 now slicereg algo option is insensitive to case
BUG: fixed #232 now slicereg algo option is insensitive to case

Former-commit-id: 471a98a4a7a29faa76deabe1d9f5f15f4f46c1bd [formerly 5fc6c1dff5ee402152353e9ad51dd74053a0ee28]
Former-commit-id: b450020e84a3d60c8d295bf17d84964155acce40
Former-commit-id: 450d207a8660ca6e2b0a6d7cb04d0ec76ee4a1c0
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox