Various Improvements

[kahrendt]

Small PR that fix some bugs and various improvements:

• Add command line argument to specify which weights to use ('best_weights' or 'last_weights')
• Move the strided drop layer to its own file (potentially other model architectures can use it more easily)
• Simplify test logic using inference.py
• Fix a bug where the testing_ambient metrics overwrote the testing metrics for streaming models
• Various code formatting improvements