Add shooter class and python.

Change-Id: I27b4c8f282a0b80344a7df59cf3b04569d9c8110
diff --git a/y2020/control_loops/superstructure/superstructure_goal.fbs b/y2020/control_loops/superstructure/superstructure_goal.fbs
index bade51e..f26b076 100644
--- a/y2020/control_loops/superstructure/superstructure_goal.fbs
+++ b/y2020/control_loops/superstructure/superstructure_goal.fbs
@@ -5,10 +5,10 @@
 table ShooterGoal {
   // Angular velocity in rad/s of the slowest (lowest) wheel in the kicker.
   // Positive is shooting the ball.
-  velocity_kicker:double;
+  velocity_accelerator:double;
 
   // Angular velocity in rad/s of the flywheel. Positive is shooting.
-  velocity_flywheel:double;
+  velocity_finisher:double;
 }
 
 table Goal {