Allow puppet to configure Gerrit's gitHttpUrl option

Gerrit 2.11 has a gerrit.gitHttpUrl[1] option that will display an
alternative git repo location to users.

[1] https://review.openstack.org/Documentation/config-gerrit.html#gerrit.gitHttpUrl

Change-Id: I4fa1cc7b1f0b717c35dc4eccedb635c9f3680c26

manifests/init.pp

@@ -12,6 +12,8 @@
 #   canonicalweburl:
 #     Used in the Gerrit config to generate links,
 #       eg., https://review.example.com/
+#   git_http_url:
+#     Optional base URL for repositories available over the HTTP protocol
 #   ssl_cert_file:
 #   ssl_key_file:
 #     Used in the Apache virtual host to specify the SSL cert and key files.
@@ -127,6 +129,7 @@ class gerrit(
   $vhost_name = $::fqdn,
   $redirect_to_canonicalweburl = true,
   $canonicalweburl = "https://${::fqdn}/",
+  $git_http_url = '',
   $robots_txt_source = '', # If left empty, the gerrit default will be used.
   $serveradmin = "webmaster@${::fqdn}",
   $ssl_cert_file = '/etc/ssl/certs/ssl-cert-snakeoil.pem',
@@ -338,6 +341,7 @@ class gerrit(
   # Template uses:
   # - $mysql_host
   # - $canonicalweburl
+  # - $git_http_url
   # - $smtpserver
   # - $sendemail_from
   # - $sendemail_include_diff

templates/gerrit.config.erb

@@ -7,6 +7,9 @@
 	changeScreen = OLD_UI
 	reportBugText = <%= @report_bug_text %>
 	reportBugUrl = <%= @report_bug_url %>
+<% if @git_http_url != "" -%>
+	gitHttpUrl = <%= @git_http_url %>
+<% end -%>
 [database]
 	type = MYSQL
 	hostname = <%= @mysql_host %>