Adding target point definition and calculation (x,y,radius) for visualization

Apologies in advance for:
1) Changing flatbuffer definitions
1a) Moved to camera poses, since I think it really belongs there
1b) Changed name of target, since it had same name as those in trainging data
2) A lot of formatting from running yapf, buildifier, clang-format.
(BUILD, target_definition_test.py have formatting changes only)
(define_training_data.py and load_sift_training.py are mostly formatting)

Change-Id: Iace1261ea5f04aeb8103b5b9a9d6da5ec3328293
diff --git a/y2020/vision/sift/sift.fbs b/y2020/vision/sift/sift.fbs
index 43ea152..3e2daaf 100644
--- a/y2020/vision/sift/sift.fbs
+++ b/y2020/vision/sift/sift.fbs
@@ -133,6 +133,12 @@
 
   // The pose of the camera in the field coordinate frame
   field_to_camera:TransformationMatrix;
+
+  // 2D image coordinate representing target location on the matched image
+  query_target_point_x:float;
+  query_target_point_y:float;
+  // Perceived radius of target circle
+  query_target_point_radius:float;
 }
 
 table ImageMatchResult {
@@ -153,10 +159,6 @@
 
   // Information about the camera which took this image.
   camera_calibration:CameraCalibration;
-
-  // 2D image coordinate representing target location on the matched image
-  target_point_x:float;
-  target_point_y:float;
 }
 
 root_type ImageMatchResult;