Merge branch 'testing' of gitorious.org:statusnet/mainline into testing

* 'testing' of gitorious.org:statusnet/mainline:
  Localization tweak: include doc comments marked as 'TRANS' in .po file output; these should now get automatically pulled through to the TranslateWiki interface as translator help hints.
  Add index on group_index.notice_id, needed to pull list of target groups for inbox delivery.
  Add index on post_id for file_to_post, needed for efficient lookups of files/urls attached to a given post.
  Update pot file