Thread: pgsql: Elaborate on what gets stored in pg_authid.rolpasswd.

Log Message:
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Elaborate on what gets stored in pg_authid.rolpasswd.

Also, add cross-reference from pg_shadow.passwd to pg_authid.rolpasswd and
fix a bit of markup I muffed in my previous commit.

Per discussion with Josh Kupershmidt.

Modified Files:
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    pgsql/doc/src/sgml:
        catalogs.sgml (r2.229 -> r2.230)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/catalogs.sgml?r1=2.229&r2=2.230)