saved, that is before insertNewArticle() is called
&$editpage_Obj: the current EditPage object
+'EditPage::importFormData': allow extensions to read additional data
+posted in the form
+$editpage: EditPage instance
+$request: Webrequest
+return value is ignored (should always return true)
+
'EditPage::showEditForm:fields': allows injection of form field into edit form
&$editor: the EditPage instance for reference
&$out: an OutputPage instance to write to