Provide a "default moderate" option for comments. The default behavior

is unchanged, but you now have the option to set all new comments to
be unpublished and then moderate them through the Admin > Content >
Comments interface.

Fixes #2126.

modules/comment/css/comment.css

@@ -43,3 +43,7 @@
   padding: .2em .6em;
 }
 
+.g-comment-state-unpublished {
+  font-style: italic;
+  color: #999;
+}