Add the ability to set zuul's gerrit baseurl

Change-Id: Ieb9fd71776dd69e9f01df1f565d5ca6951d6dd97

modules/zuul/manifests/init.pp

@@ -24,6 +24,7 @@ class zuul (
   $internal_gearman = true,
   $gerrit_server = '',
   $gerrit_user = '',
+  $gerrit_baseurl = '',
   $zuul_ssh_private_key = '',
   $url_pattern = '',
   $status_url = "https://${::fqdn}/",

modules/zuul/templates/zuul.conf.erb

@@ -9,6 +9,9 @@ log_config=/etc/zuul/gearman-logging.conf
 server=<%= gerrit_server %>
 user=<%= gerrit_user %>
 sshkey=/var/lib/zuul/ssh/id_rsa
+<% if gerrit_baseurl != "" -%>
+baseurl=<%= gerrit_baseurl %>
+<% end -%>
 
 [zuul]
 layout_config=/etc/zuul/layout.yaml