Add default commitMessage text and date generated field to Staticman config

_config.yml

@@ -31,12 +31,18 @@ comments:
 staticman:
   allowedFields          : ['name', 'email', 'url', 'message']
   branch                 : # "master", "gh-pages"
+  commitMessage          : "New comment."
   format                 : "yml"
   moderation             : true
   path                   : "_data/comments/{options.slug}"
   requiredFields         : ['name', 'email', 'message']
   transforms:
     email                : "md5"
+  generatedFields:
+    date:
+      type               : "date"
+      options:
+        format           : "iso8601" # "iso8601" (default), "timestamp-seconds", "timestamp-milliseconds"
 atom_feed:
   path                   : # blank (default) uses feed.xml