Note overlay config ordering

doc/man/man5/slapd.conf.5

@@ -1309,7 +1309,8 @@ code that intercepts database operations in order to extend or change
 them. Overlays are pushed onto
 a stack over the database, and so they will execute in the reverse
 of the order in which they were configured and the database itself
-will receive control last of all.
+will receive control last of all. Note that all of the database's
+regular settings should be configured before any overlay settings.
 .TP
 .B readonly on | off
 This option puts the database into "read-only" mode.  Any attempts to