Modify third robot code at Madera.

This is the code that was running on 9971 by the end of the
copetition. It's a little kludgy, (mainly the work-arounds
for not having a gyro board), but I decided to commit it
anyway.

There were many changes, but the most important were
probably these:

- Get autonomous to actually work.
- Trick the control loop into giving the shooter 12 volts after
every shot in order to spin it back up.
- Make sure it either powers the shooter or the drivetrain
and not both, so that the shooter wheel can't run so slowly that
frisbees get stuck.
diff --git a/bot3/control_loops/drivetrain/drivetrain.h b/bot3/control_loops/drivetrain/drivetrain.h
index 03b3bd0..40bddf7 100644
--- a/bot3/control_loops/drivetrain/drivetrain.h
+++ b/bot3/control_loops/drivetrain/drivetrain.h
@@ -8,13 +8,13 @@
 namespace control_loops {
 
 class DrivetrainLoop
-    : public aos::control_loops::ControlLoop<control_loops::Drivetrain> {
+    : public aos::control_loops::ControlLoop<control_loops::Drivetrain, false> {
  public:
   // Constructs a control loop which can take a Drivetrain or defaults to the
   // drivetrain at frc971::control_loops::drivetrain
   explicit DrivetrainLoop(
-      control_loops::Drivetrain *my_drivetrain = &control_loops::drivetrain)
-      : aos::control_loops::ControlLoop<control_loops::Drivetrain>(
+      control_loops::Drivetrain *my_drivetrain = &::bot3::control_loops::drivetrain)
+      : aos::control_loops::ControlLoop<control_loops::Drivetrain, false>(
           my_drivetrain) {}
 
  protected: