Log Message:
-----------
Improve description of bgwriter_lru_multiplier, per discussion.
Modified Files:
--------------
pgsql/doc/src/sgml:
config.sgml (r1.160 -> r1.161)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/config.sgml?r1=1.160&r2=1.161)