DOC: renamed install_ants to install_ants_osx, anticipating that there will be one for debian/ubuntu
DOC: renamed install_ants to install_ants_osx, anticipating that there will be one for debian/ubuntu

3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox