Drive code works on Tantrum.

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

Change-Id: Id589acdc443dcd81242a21e3b0c26f81d6974dc8
diff --git a/frc971/control_loops/drivetrain/drivetrain.cc b/frc971/control_loops/drivetrain/drivetrain.cc
index b4a23c3..14c1a42 100644
--- a/frc971/control_loops/drivetrain/drivetrain.cc
+++ b/frc971/control_loops/drivetrain/drivetrain.cc
@@ -29,7 +29,7 @@
 namespace drivetrain {
 
 DrivetrainLoop::DrivetrainLoop(
-    const DrivetrainConfig &dt_config,
+    const DrivetrainConfig<double> &dt_config,
     ::frc971::control_loops::DrivetrainQueue *my_drivetrain)
     : aos::controls::ControlLoop<::frc971::control_loops::DrivetrainQueue>(
           my_drivetrain),