Fix documentation in fridge.q and actions.

Austin made zero on the arm sticking straight up, and the comments
in fridge.q ended up being wrong. I fixed these comments, as well
as the actions that I had written based on them.

I also made the comments in fridge.q about zero on the elevator
match the ones in constants.cc.

Change-Id: Ie50c99f6cafc82f0e4baba851cd20353a9d871ac
diff --git a/frc971/actors/score_actor.cc b/frc971/actors/score_actor.cc
index 25edbff..0ab54de 100644
--- a/frc971/actors/score_actor.cc
+++ b/frc971/actors/score_actor.cc
@@ -52,13 +52,13 @@
 
   // We're going to move the elevator first so we don't crash the fridge into
   // the ground.
-  DoProfile(values.fridge.arm_zeroing_height, M_PI / 2.0, true);
+  DoProfile(values.fridge.arm_zeroing_height, 0.0, true);
   // Now move them both together.
-  DoProfile(params.height, M_PI, true);
+  DoProfile(params.height, M_PI / 2.0, true);
   // Release the totes.
-  DoProfile(values.fridge.arm_zeroing_height, M_PI / 2.0, false);
+  DoProfile(values.fridge.arm_zeroing_height, 0.0, false);
   // Retract. Move back to our lowered position.
-  DoProfile(values.fridge.elevator.lower_limit, M_PI / 2.0, false);
+  DoProfile(values.fridge.elevator.lower_limit, 0.0, false);
 
   return true;
 }
diff --git a/frc971/actors/stack_actor.cc b/frc971/actors/stack_actor.cc
index ff9c739..6ce8fbd 100644
--- a/frc971/actors/stack_actor.cc
+++ b/frc971/actors/stack_actor.cc
@@ -28,7 +28,7 @@
   params.elevator_max_velocity = kElevatorMaxVelocity;
   params.elevator_max_acceleration = kElevatorMaxAccel;
 
-  params.arm_angle = M_PI / 2.0;
+  params.arm_angle = 0.0;
   params.arm_max_velocity = kArmMaxVelocity;
   params.arm_max_acceleration = kArmMaxAccel;
 
diff --git a/frc971/control_loops/fridge/fridge.q b/frc971/control_loops/fridge/fridge.q
index be54ee7..f8fa16e 100644
--- a/frc971/control_loops/fridge/fridge.q
+++ b/frc971/control_loops/fridge/fridge.q
@@ -15,13 +15,14 @@
 queue_group FridgeQueue {
   implements aos.control_loops.ControlLoop;
 
-  // All angles are in radians with 0 sticking straight out horizontally over
-  // the intake (the front). Rotating up and into the robot (towards the back
+  // All angles are in radians with 0 sticking straight up.
+  // Rotating up and into the robot (towards the back
   // where boxes are placed) is positive. Positive output voltage moves all
   // mechanisms in the direction with positive sensor values.
 
-  // Elevator heights are the vertical distance (in meters) from the top of the
-  // frame (at the front and back) to the axis of the bottom pivot of the arm.
+  // Elevator heights are the vertical distance (in meters) from a defined zero.
+  // In this case, zero is where the portion of the carriage that Spencer
+  // removed lines up with the bolt.
 
   message Goal {
     // Angle of the arm.
@@ -47,7 +48,7 @@
   message Status {
     // Are both the arm and elevator zeroed?
     bool zeroed;
-    
+
     // Angle of the arm.
     double angle;
     // Height of the elevator.