Upgraded //y2015 to use the common drive code.

This is a fixup from changing the call signature of DoCoerceGoal

Change-Id: I8536f4cd793370cec8d369a00e4fc34b35442fd3
diff --git a/y2015/joystick_reader.cc b/y2015/joystick_reader.cc
index 4b5ced8..7cbd7e5 100644
--- a/y2015/joystick_reader.cc
+++ b/y2015/joystick_reader.cc
@@ -12,7 +12,7 @@
 #include "aos/common/actions/actions.h"
 
 #include "y2015/control_loops/claw/claw.q.h"
-#include "y2015/control_loops/drivetrain/drivetrain.q.h"
+#include "frc971/control_loops/drivetrain/drivetrain.q.h"
 #include "y2015/control_loops/fridge/fridge.q.h"
 #include "y2015/constants.h"
 #include "frc971/queues/gyro.q.h"