Wordpress Demo Improvements

The HTTP_X_FORWARDED_PROTO server check no longer causes an error when running wp-cli. Settings for the WordPress demo have been add to the docker-compose.yml file. They are commented out and need to be enabled in order to install wp-cli and to set the working directory of the container to /var/www/public. curl is now used to download WordPress when creating the demo using docker-create-project wordpress.