$ wget -q https://raw.githubusercontent.com/petervanderdoes/gitflow-avh/develop/contrib/gitflow-installer.sh && sudo bash gitflow-installer.sh install stable; rm gitflow-installer.sh
$ wget -q -O - --no-check-certificate https://github.com/nvie/gitflow/raw/develop/contrib/gitflow-installer.sh | bash
$ wget -q https://raw.githubusercontent.com/petervanderdoes/gitflow-avh/develop/contrib/gitflow-installer.sh && sudo bash gitflow-installer.sh install stable; rm gitflow-installer.sh