$isbn: ISBN to show information for
$output: OutputPage object in use
+'CanIPUseHTTPS': Determine whether the client at a given source IP is likely
+to be able to access the wiki via HTTPS.
+$ip: The IP address in human-readable form
+&$canDo: This reference should be set to false if the client may not be able
+to use HTTPS
+
'CanonicalNamespaces': For extensions adding their own namespaces or altering
the defaults.
Note that if you need to specify namespace protection or content model for
$add : Array of strings corresponding to groups added
$remove: Array of strings corresponding to groups removed
+'UserRequiresHTTPS': Called to determine whether a user needs
+to be switched to HTTPS.
+$user: User in question.
+&$https: Boolean whether $user should be switched to HTTPS.
+
+
'UserRetrieveNewTalks': Called when retrieving "You have new messages!"
message(s).
$user: user retrieving new talks messages