Log Message:
-----------
Update PITR mention of which WAL files are needed.
Modified Files:
--------------
pgsql/doc/src/sgml:
backup.sgml (r2.61 -> r2.62)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/backup.sgml.diff?r1=2.61&r2=2.62)