Point child link to the search page rather than a non-existent anchor
Clear message fields after sending a message (fixes #353)
Attempt to tackle more subtle bugs in the search ordering behaviour.

 - Default search ordering fallback is now a separate parameter
   to the find() function, which makes it easier to override
 - The search order isn't added to the search form unless it's actually
   in the parameters
Merge branch 'master' into virtual_collection_rework