Drive code works on Tantrum.

Need to write the spring code.  Drive now supports doubles...  What a
pain.

Change-Id: Id589acdc443dcd81242a21e3b0c26f81d6974dc8
diff --git a/y2017/control_loops/drivetrain/drivetrain_base.cc b/y2017/control_loops/drivetrain/drivetrain_base.cc
index af3ff38..b351cbf 100644
--- a/y2017/control_loops/drivetrain/drivetrain_base.cc
+++ b/y2017/control_loops/drivetrain/drivetrain_base.cc
@@ -18,8 +18,8 @@
 
 const ShifterHallEffect kThreeStateDriveShifter{0.0, 0.0, 0.25, 0.75};
 
-const DrivetrainConfig &GetDrivetrainConfig() {
-  static DrivetrainConfig kDrivetrainConfig{
+const DrivetrainConfig<double> &GetDrivetrainConfig() {
+  static DrivetrainConfig<double> kDrivetrainConfig{
       ::frc971::control_loops::drivetrain::ShifterType::NO_SHIFTER,
       ::frc971::control_loops::drivetrain::LoopType::CLOSED_LOOP,
       ::frc971::control_loops::drivetrain::GyroType::IMU_Z_GYRO,