Log Message:-----------Small wording improvements for source code READMEs.
Modified Files:-------------- pgsql/src/backend/optimizer: README (r1.45 -> r1.46) (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/README?r1=1.45&r2=1.46) pgsql/src/backend/parser: README (r1.9 -> r1.10) (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/README?r1=1.9&r2=1.10) pgsql/src/backend/utils/mmgr: README (r1.14 -> r1.15) (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mmgr/README?r1=1.14&r2=1.15)