Allow lagged external storage
Do not tidy user interface messages
Fix revision fetching query (propagate equality manually :)
* (bug 4686) Fix regression where ?diff=0&oldid=0 caused fatal error on
pages with only one revision. Fixes message diff link on first edit.
* Fix dependence on hardcoded UNIQ_PREFIX in LanguageConverter.php
+* Do not check lag on external storage servers
+* Do not tidy interface messages (unless full tidy is set)
+* Do not trust equality propagation and give more hints to MySQL
+ optimizer for revision fetches (avoids index scans)
=== Caveats ===