The vhost::proxy vhost template file uses the ssl_path var.
Unfortuantely this isn't defined in params so we get errors like:
Unknown variable: 'httpd::params::ssl_path'. at /etc/puppetlabs/code/modules/httpd/manifests/vhost/proxy.pp:37:15
Fix that by defining a value. Note this value should be correct for
debuntu, but is probably wrong for RHEL/CentOS.
Change-Id: Idbb1ac60a17d5506c4dd0d19eb10c1a45741c3b5
c629d4779a