$software: The array of software in format 'name' => 'version'. See
SpecialVersion::softwareInformation().
+'SpecialBlockModifyFormFields': Add more fields to Special:Block
+$sp: SpecialPage object, for context
+&$fields: Current HTMLForm fields
+
'SpecialContributionsBeforeMainOutput': Before the form on Special:Contributions
$id: User identifier