Add Charles Proxy recipe

This adds a recipe to install Charles Proxy - http://www.charlesproxy.com/

If a license key and license name are specified in the node attributes config, then a configuration file will be generated and pre-filled with the license info, so the application is fully registered on first run. Rather handy if you have a site license!

    node_attributes:
      charles_proxy:
        license_name: Your Name
        license_key: 7ad6c7a6c87...