Code Cleanup and Improved Tests

[kozlov721]

DevOps

• Synced the CI pipeline with the one in luxonis-ml
  • Added automatic labeler and assigner
• Removed MacOS tests because they're running out of memory
• Added type checking requirement
• Set the minimum coverage to 90 %
• Updated information in CONTRIBUTING.md
• Changed formatter settings to conform to PEP 8

Cleanup

• Removed dead code
• Added missing docs
• Added missing types
• Some modules moved and renamed
  • Loaders, assigners, callbacks and schedulers moved from luxonis_train.utils to luxonis_train
  • luxonis_train.utils better organized
• Changed types of some raised exceptions
• Improved error messages

Tests

• Increased coverage to 97 %
• Added sanity tests for every backbone/head combination
  • Groundwork for overfit tests, can be turned on by specifying LUXONIS_TRAIN_OVERFIT env variable, but not yet reliable

Fixes

• Fixed SmoothBCEWithLogitsLoss
• Fixed SoftmaxFocalLoss
  • Removed incorrect multiclass implementation
  • Currently both focal losses only support binary tasks, support for multiclass will be added later

Changes

• Added GradientAccumulationScheduler, StochasticWeightAveraging, Timer, and ModelPruning callbacks to the callback REGISTRY
• added trainer.deterministic option to the config file as a way to use "warn" option for models incompatible with determinism
• added size_multiplier option to luxonis_train inspect CLI command to better display large images
• removed the Protocol pattern from BaseNode
• added F1 score to MeanAveragePrecision for bounding boxes

Discovered Issues

• The ImplicitKeypointBBoxHead does not train
  • Wasn't able to find out why
  • Will address in a separate PR
  • For now, changed the default keypoint head in the predefined keypoint model to EfficientKeypointBBoxHead
    • That one was more performant anyways as far as I know