build testing circuits more rapidly. this has a failure mode

where if circuits fail quickly, we'll fail a lot of them very
quickly and not retry for a while. so be it.


svn:r8407

src/or/circuituse.c

@@ -653,12 +653,12 @@ circuit_testing_opened(origin_circuit_t *circ)
 static void
 circuit_testing_failed(origin_circuit_t *circ, int at_last_hop)
 {
-  if (server_mode(get_options()) && check_whether_orport_reachable())
-    return;
-
   log_info(LD_GENERAL,
            "Our testing circuit (to see if your ORPort is reachable) "
-           "has failed. I'll try again later.");
+           "has failed. Considering launching another one.");
+
+  if (!circuit_enough_testing_circs())
+    consider_testing_reachability(1, 0);
 
   /* These aren't used yet. */
   (void)circ;