Support operator*/-> in new flatbuffers API

This was suggested during the initial reviews, and does seem to reduce a
fair amount of overhead.

Change-Id: Icb22106612c3a8430afa0b9dbe0a85f835e5b821
Signed-off-by: James Kuszmaul <james.kuszmaul@bluerivertech.com>
diff --git a/aos/events/event_loop_param_test.cc b/aos/events/event_loop_param_test.cc
index bfce034..5ec494f 100644
--- a/aos/events/event_loop_param_test.cc
+++ b/aos/events/event_loop_param_test.cc
@@ -119,7 +119,7 @@
 
     aos::Sender<TestMessageStatic>::StaticBuilder msg =
         sender.MakeStaticBuilder();
-    msg.get()->set_value(200);
+    msg->set_value(200);
     CHECK(msg.builder()->Verify());
     msg.CheckOk(msg.Send());
   });