Add ids to flatbuffer fields in y2012, y2016, frc971, and aos

Change-Id: I9ed9006ce6224e2df0459df47771786b928164a1
diff --git a/frc971/codelab/basic_position.fbs b/frc971/codelab/basic_position.fbs
index 1420313..72d80d2 100644
--- a/frc971/codelab/basic_position.fbs
+++ b/frc971/codelab/basic_position.fbs
@@ -6,7 +6,7 @@
   // ball in, and the ball then hits a limit sensor when it is fully contained.
   // We would then want to stop running the intake to avoid spinning the intake
   // against the ball.
-  limit_sensor: bool;
+  limit_sensor: bool (id: 0);
 }
 
 root_type Position;