Inline documentation for hooks in wp-includes/feed-rdf.php.

props dustyf.
see #25229.

git-svn-id: http://develop.svn.wordpress.org/trunk@25479 602fd350-edb4-49c9-b593-d223f7449a82
Inline documentation for hooks in wp-links-opml.php.

props netweb.
see #25229.

git-svn-id: http://develop.svn.wordpress.org/trunk@25480 602fd350-edb4-49c9-b593-d223f7449a82
Inline documentation for hooks in wp-admin/includes/ms.php.

props enej, DrewAPicture.
see #25229.

git-svn-id: http://develop.svn.wordpress.org/trunk@25481 602fd350-edb4-49c9-b593-d223f7449a82