Log Message:
-----------
Add comments about definitions that may affect PG_CONTROL_VERSION,
per recent unintended-initdb-forcing fiasco
Modified Files:
--------------
pgsql/src/include/catalog:
pg_control.h (r1.56 -> r1.57)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_control.h?r1=1.56&r2=1.57)