Log Message:
-----------
Add credit to Pavel Stehule for XML functionality
Modified Files:
--------------
pgsql/doc/src/sgml:
release.sgml (r1.555 -> r1.556)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/release.sgml?r1=1.555&r2=1.556)