Better way to manage updating the wiki. * Make the difference between updating just a single page, and updating the whole wiki. * Properly resolve a just-updated page, but postpone resolving all the rest if we're using background updates. * Don't flatten single metas for the web UI.

--- a/wikked/tasks.py	Mon Mar 24 23:05:19 2014 -0700
+++ b/wikked/tasks.py	Tue Mar 25 22:09:14 2014 -0700
@@ -34,5 +34,5 @@
 @app.task
 def update_wiki(wiki_root):
     with wiki_session(wiki_root) as wiki:
-        wiki.update()
+        wiki._postSetPageUpdate()