Allow puppet to configure the Gerrit's garbage collection options

Setup puppet to schedule Gerrit's git garbage collection options[1].

[1] https://gerrit-documentation.storage.googleapis.com/Documentation/
        2.11/config-gerrit.html#gc

Change-Id: I73166de7008ceb42db3db4a8b22fb6e9c94e790d

manifests/init.pp

@@ -32,6 +32,10 @@
 #   database_poollimit:
 #   container_heaplimit:
 #   container_javaoptions:
+#   gc_start_time:
+#     Start time to define the first execution of the git garbage collection
+#   gc_interval:
+#     Interval for periodic repetition of triggering the git garbage collection
 #   core_loggingbuffersize:
 #   core_packedgitopenfiles:
 #   core_packedgitlimit:
@@ -147,6 +151,8 @@ class gerrit(
   $database_poollimit = '',
   $container_heaplimit = '',
   $container_javaoptions = '',
+  $gc_start_time = '',
+  $gc_interval = '',
   $core_loggingbuffersize = '',
   $core_packedgitlimit = '',
   $core_packedgitopenfiles = '',
@@ -328,6 +334,8 @@ class gerrit(
   # - $java_home
   # - $container_heaplimit
   # - $container_javaoptions
+  # - $gc_start_time
+  # - $gc_interval
   # - $core_packedgitopenfiles
   # - $core_packedgitlimit
   # - $core_packedgitwindowsize

templates/gerrit.config.erb

@@ -51,6 +51,13 @@
 <% if @container_heaplimit != "" -%>
 	heapLimit = <%= @container_heaplimit %>
 <% end -%>
+[gc]
+<% if @gc_start_time != "" -%>
+	startTime = <%= @gc_start_time %>
+<% end -%>
+<% if @gc_interval != "" -%>
+	interval = <%= @gc_interval %>
+<% end -%>
 [core]
 <% if @core_loggingbuffersize != "" -%>
 	asyncLoggingBufferSize = <%= @core_loggingbuffersize %>