Trace when gracefully shutting down immediately

Feersum.xs

@@ -2049,6 +2049,7 @@ graceful_shutdown (SV *self, SV *cb)
     close(accept_w.fd);
 
     if (active_conns <= 0) {
+        trace("shutdown is immediate\n");
         dSP;
         ENTER;
         SAVETMPS;

TODO

@@ -31,13 +31,6 @@ Handle requests that don't require a body (optional entities).
     start (not sure if there's a PSGI-compatible way to do this)
     * different request timeout logic will be needed.
 
-Per-client "drain" and "completion" callbacks?
-
-    * drain sorta done as the $w->poll_cb()
-    * completion_cb is called when finished sending a full HTTP response.  For
-    non-KA a guard on the conn object is sufficient, but for KA a callback is
-    needed.
-
 Optimize env-hash
 
     * allow Feersum apps to specify which vars will be needed (v1.1)