fixed author/email handling in RSS/Atom feeds

1) Now reports full user name for logged in users
2) Reports actual email when not mail guarding; otherwise it's "user@ip"
3) RSS 1.0 (default) format is now <dc:creator>name (email)</dc:creator>
4) RSS 0.91/RSS 2.0 format is now <author>email (name)</author>
5) Atom format is now <author><name>name</name><email>email</email></author>
6) When anonymous, all RSS formats just reports "user@ip" in element
7) When anonymous, Atom just reports <author><email>user@ip</email></author>

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