This cartridge installs PhantomJS and CasperJS.
Install cartridge via "Install your own Cartridge" using the link https://raw.githubusercontent.com/daniel-sc/casperjs-cartridge/master/metadata/manifest.yml .
SSH into your gear and check if its working:
`echo $OPENSHIFT_CASPERJS_BIN_DIR`casperjs --version
`echo $PHANTOMJS_EXECUTABLE` -v
(You might need to restart the app to have the environment variables available)