Log Message:
-----------
Move SYMMETRIC/ASYMMETRIC to reserved words to avoid shift/reduce conflicts.
Modified Files:
--------------
pgsql/src/backend/parser:
gram.y (r2.493 -> r2.494)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/gram.y.diff?r1=2.493&r2=2.494)