Rewrited function update_slice.
Rewrited function update_slice.


Former-commit-id: bc0e65fff655f93040ab569f549307ed4c605091
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox