'DatabaseOraclePostInit': Called after initialising an Oracle database
&$db: the DatabaseOracle object
+'Debug': called when outputting a debug log line via wfDebug() or wfDebugLog()
+$text: plaintext string to be output
+$group: null or a string naming a logging group (as defined in $wgDebugLogGroups)
+
'NewDifferenceEngine': Called when a new DifferenceEngine object is made
$title: the diff page title (nullable)
&$oldId: the actual old Id to use in the diff