Move some DrivetrainConfig types to flatbuffers

This makes it so that we can start to implement the DrivetrainConfig as
a flatbuffer.

Change-Id: I69b92fcc436e82662d01a329d048a80c67267267
Signed-off-by: James Kuszmaul <jabukuszmaul+collab@gmail.com>
diff --git a/motors/simpler_receiver.cc b/motors/simpler_receiver.cc
index 7fad0b8..2724f3b 100644
--- a/motors/simpler_receiver.cc
+++ b/motors/simpler_receiver.cc
@@ -27,14 +27,14 @@
 
 namespace chrono = ::std::chrono;
 
-const ShifterHallEffect kThreeStateDriveShifter{0.0, 0.0, 0.25, 0.75};
+const ShifterHallEffect kThreeStateDriveShifter{{}, 0.0, 0.0, 0.25, 0.75};
 
 const DrivetrainConfig<float> &GetDrivetrainConfig() {
   static DrivetrainConfig<float> kDrivetrainConfig{
-      ::frc971::control_loops::drivetrain::ShifterType::NO_SHIFTER,
-      ::frc971::control_loops::drivetrain::LoopType::OPEN_LOOP,
-      ::frc971::control_loops::drivetrain::GyroType::SPARTAN_GYRO,
-      ::frc971::control_loops::drivetrain::IMUType::IMU_X,
+      ::frc971::control_loops::drivetrain::ShifterType::kNoShifter,
+      ::frc971::control_loops::drivetrain::LoopType::kOpenLoop,
+      ::frc971::control_loops::drivetrain::GyroType::kSpartanGyro,
+      ::frc971::control_loops::drivetrain::ImuType::kImuX,
 
       ::motors::seems_reasonable::MakeDrivetrainLoop,
       ::motors::seems_reasonable::MakeVelocityDrivetrainLoop,