Add more status information to spline following

Change-Id: I2cafd5b35107a64789473c4c5a6b307d95f51dea
Signed-off-by: James Kuszmaul <jabukuszmaul+collab@gmail.com>
diff --git a/frc971/control_loops/drivetrain/splinedrivetrain.h b/frc971/control_loops/drivetrain/splinedrivetrain.h
index f02a5b6..24fb66c 100644
--- a/frc971/control_loops/drivetrain/splinedrivetrain.h
+++ b/frc971/control_loops/drivetrain/splinedrivetrain.h
@@ -105,6 +105,9 @@
 
   // Information used for status message.
   ::Eigen::Matrix<double, 2, 1> uncapped_U_;
+  ::Eigen::Matrix<double, 5, 1> last_state_error_;
+  ::Eigen::Matrix<double, 2, 5> last_U_components_;
+  ::Eigen::Matrix<double, 2, 1> last_U_ff_;
   bool enable_ = false;
   bool output_was_capped_ = false;
 };