Standardize license headers in TOML/YAML files (#13491)

Refactor code for speed and clarity

Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

data/ImageNet.yaml

@@ -1,4 +1,5 @@
-# Ultralytics YOLOv5 🚀, AGPL-3.0 license
+# Ultralytics 🚀 AGPL-3.0 License - https://ultralytics.com/license
+
 # ImageNet-1k dataset https://www.image-net.org/index.php by Stanford University
 # Simplified class names from https://github.com/anishathalye/imagenet-simple-labels
 # Example usage: python classify/train.py --data imagenet