Log Message:
-----------
Document how pglesslog can be used to reduce the storage requirements of PITR.
Modified Files:
--------------
pgsql/doc/src/sgml:
backup.sgml (r2.121 -> r2.122)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/backup.sgml?r1=2.121&r2=2.122)