Update dataset names from array to dictionary (#9000)

* Migrate dataset names to dictionary

* fix check

* backwards compat

* predict fix

* val fix

* Keep dataset stats behavior identical

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

data/VisDrone.yaml

@@ -14,8 +14,17 @@ val: VisDrone2019-DET-val/images  # val images (relative to 'path')  548 images
 test: VisDrone2019-DET-test-dev/images  # test images (optional)  1610 images
 
 # Classes
-nc: 10  # number of classes
-names: ['pedestrian', 'people', 'bicycle', 'car', 'van', 'truck', 'tricycle', 'awning-tricycle', 'bus', 'motor']
+names:
+  0: pedestrian
+  1: people
+  2: bicycle
+  3: car
+  4: van
+  5: truck
+  6: tricycle
+  7: awning-tricycle
+  8: bus
+  9: motor
 
 
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