Add a basic class-level comment to the blog html export.

htdocs/artefact/blog/export/html/lib.php

@@ -26,6 +26,9 @@
 
 defined('INTERNAL') || die();
 
+/**
+ * Dumps all of the user's blogs as static HTML
+ */
 class HtmlExportBlog extends HtmlExportArtefactPlugin {
 
     private $blogcount;