Installs the Crunchy Bridge CLI onto your Heroku dynos. Will by default download the latest version available in the Github releases list, but can be pinned to a specific version.
To pin the installed CLI to a specific release create a .crunchy_cli_version file in the root directory of your application. Include the version string for the desired version in this file; for example: v3.6.6. Include the "v" since this script will match the release version explicitly against the Github release tags.