Log Message:
-----------
Add contraint exclusion section to contraint docs.
Takahiro Itagaki
Modified Files:
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pgsql/doc/src/sgml:
ddl.sgml (r1.90 -> r1.91)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ddl.sgml?r1=1.90&r2=1.91)