Add shooter class and python.

Change-Id: I27b4c8f282a0b80344a7df59cf3b04569d9c8110
diff --git a/y2020/control_loops/superstructure/superstructure_position.fbs b/y2020/control_loops/superstructure/superstructure_position.fbs
index 63f91c7..ed4ba18 100644
--- a/y2020/control_loops/superstructure/superstructure_position.fbs
+++ b/y2020/control_loops/superstructure/superstructure_position.fbs
@@ -4,12 +4,12 @@
 
 table ShooterPosition {
   // Flywheel angle in radians, positive is shooting.
-  theta_flywheel:double;
+  theta_finisher:double;
 
   // Kicker angle in radians of the slowest (lowest) wheel, positive is
   // accelerating the ball toward the shooter.
-  theta_kicker_left:double;
-  theta_kicker_right:double;
+  theta_accelerator_left:double;
+  theta_accelerator_right:double;
 }
 
 table Position {