Tweak consumer to use the new disconnect_cb

Signed-off-by: Pedro Melo <melo@simplicidade.org>

examples/consumer.pl

@@ -22,7 +22,8 @@ my $r = AnyEvent::NSQ::Reader->new(
 #  message_cb => sub {print STDERR "$c: $_[1]{message}\n";$c++; return},    ## return undef => mark_as_done_msg()
   message_cb => sub {return},    ## return undef => mark_as_done_msg()
 
-  error_cb => sub { warn "$_[1] --- exiting...\n"; $cv->send },
+  error_cb      => sub { warn "$_[1]\n" },
+  disconnect_cb => sub { warn "Got disconnected... exiting...\n"; $cv->send },
 );
 
 $cv->recv;