db: moved pg-only code out of interfaces module

collects/db/private/generic/interfaces.rkt

@@ -14,7 +14,6 @@
          define-type-table
 
          no-cache-prepare<%>
-         connector<%>
 
          locking%
          transactions%
@@ -176,16 +175,6 @@
         (list ok? t x)))))
 
 
-;; == Internal staging interfaces
-
-;; connector<%>
-;; Manages making connections
-(define connector<%>
-  (interface ()
-    attach-to-ports            ;; input-port output-port -> void
-    start-connection-protocol  ;; string string string/#f -> void
-    ))
-
 ;; == Notice/notification handler maker
 
 ;; make-handler : output-port/symbol string -> string string -> void

collects/db/private/postgresql/connection.rkt

@@ -14,6 +14,13 @@
 
 ;; ========================================
 
+;; connector<%>
+;; Manages making connections
+(define connector<%>
+  (interface ()
+    attach-to-ports              ;; input-port output-port -> void
+    start-connection-protocol))  ;; string string string/#f -> void
+
 (define connection-base%
   (class* transactions% (connection<%> connector<%>)
     (init-private notice-handler