Make new single wheel finisher nominally work

We now have the new 2 motor, heavy flywheel.  Update the code to have
the new inertia and also have 2 separate PWM channels to control it.

Change-Id: I2b109a0560ff499729b34a5a7e23293add4aa57c
diff --git a/y2020/constants.h b/y2020/constants.h
index e55a70b..f7d67e0 100644
--- a/y2020/constants.h
+++ b/y2020/constants.h
@@ -156,7 +156,7 @@
   static constexpr double kFinisherEncoderCountsPerRevolution() {
     return 2048.0;
   }
-  static constexpr double kFinisherEncoderRatio() { return 30.0 / 40.0; }
+  static constexpr double kFinisherEncoderRatio() { return 36.0 / 40.0; }
 
   static constexpr double kMaxFinisherEncoderPulsesPerSecond() {
     return control_loops::superstructure::finisher::kFreeSpeed / (2.0 * M_PI) *