5.1.0 Update. Avoid build collisions in the lemonade cache. Improve memory tracking and OGA testing.

[jeremyfowers]

• Avoid lemonade build cache collisions (@jeremyfowers).
  • All builds are now placed under <cache_dir>/builds/<build_name> instead of <cache_dir>/<build_name>
    • This creates a more hierarchical cache structure, where builds are peer to models and data.
  • All build names now include a timestamp
    • This ensures that build stats and logs will not collide with each other if we build the same model in the same cache, but with different parameters.
  • Revs the minor version number because all previous caches are invalidated.
• Enable ONNX model download for cpu and igpu in oga-load (@jeremyfowers)
• Improvements to memory tracking (@amd-pworfolk)
• Improve OGA testing (@jeremyfowers).
  • Run the sever test last, since it is the most complex and has the worst telemetry
  • Stop deleting the entire cache directory between every test, since that deletes the model builder cache. Instead, just delete the cache/builds directory.

[ramkrishna2910]

Looks good!