added paypal interwiki links

usage: [[paypal>email@address.com]]

conf/interwiki.conf

@@ -21,6 +21,7 @@ man       http://man.cx/
 amazon    http://www.amazon.com/exec/obidos/ASIN/{URL}/splitbrain-20/
 amazon.de http://www.amazon.de/exec/obidos/ASIN/{URL}/splitbrain-21/
 amazon.uk http://www.amazon.co.uk/exec/obidos/ASIN/
+paypal    https://www.paypal.com/cgi-bin/webscr?cmd=_xclick&business=
 phpfn     http://www.php.net/{NAME}
 coral     http://{HOST}.{PORT}.nyud.net:8090/{PATH}?{QUERY}
 freecache http://freecache.org/{NAME}