Enable SSL in groups-dev.openstack.org

Extend the Drupal vhost template with ssl capability, and
groups-dev.openstack.org now accepts the following hiera variables for
ssl setup:
- groups_dev_site_ssl_cert_file_contents: x509 certificate of vhost in pem format
- groups_dev_site_ssl_key_file_contents: rsa key of x509 certificate in pem format
- groups_dev_site_ssl_chain_file_contents: trusted chain of parent certificates (optional)

This patch is required for proper openstackid/oauth2 backref communication.

Change-Id: Ia148d1db743fc80bcb675c9ca2906333ef62eff8
Implements: blueprint groups-oauth2-authentication
Merge "Enable SSL in groups-dev.openstack.org"