Convert drivetrain mode from a bool to a number

This lets us support more than 2 drivetrain controller types in
perparation for splines.

Change-Id: I943d6073e6c5facae7223cc6111551a57b039a04
diff --git a/y2014/autonomous/auto.cc b/y2014/autonomous/auto.cc
index e5bd9bc..3ed2cd1 100644
--- a/y2014/autonomous/auto.cc
+++ b/y2014/autonomous/auto.cc
@@ -52,7 +52,7 @@
 void StopDrivetrain() {
   LOG(INFO, "Stopping the drivetrain\n");
   frc971::control_loops::drivetrain_queue.goal.MakeWithBuilder()
-      .control_loop_driving(true)
+      .controller_type(1)
       .highgear(true)
       .left_goal(left_initial_position)
       .left_velocity_goal(0)
@@ -65,7 +65,7 @@
 void ResetDrivetrain() {
   LOG(INFO, "resetting the drivetrain\n");
   ::frc971::control_loops::drivetrain_queue.goal.MakeWithBuilder()
-      .control_loop_driving(false)
+      .controller_type(0)
       .highgear(true)
       .wheel(0.0)
       .throttle(0.0)
@@ -99,7 +99,7 @@
   double right_goal = (right_initial_position + distance +
                        theta * control_loops::drivetrain::kRobotRadius);
   ::frc971::control_loops::drivetrain_queue.goal.MakeWithBuilder()
-      .control_loop_driving(true)
+      .controller_type(1)
       .highgear(true)
       .left_goal(left_goal)
       .right_goal(right_goal)