Added an option type in the parser for nifty files handing .nii and .nii.gz
Added an option type in the parser for nifty files handing .nii and .nii.gz


Former-commit-id: 49261b4c9b161d99806b93083bf3dbaf807c06e0 [formerly 66f4d2546e1b470fb31155a93f2d4a3c46baf48b]
Former-commit-id: 30bdf7041f3f23da323d61e2125d30e413a7211d
Former-commit-id: 95b4737045733d0583fbb86ce9fcdedce422d389
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox