* Update compile loss and metrics to handle multi-output dict and list
* CompileMetrics to match with per-output metrics
* Add model tests for invalid cases
* Adds unit normalization and tests
* Adds layer normalization and initial tests
* Fixes formatting in docstrings
* Fix type issues for JAX
* Fix nits
* Initial stash for group_normalization and spectral_normalization
* Adds spectral normalization and tests
* Adds group normalization and tests
* Formatting fixes
* Fix small nit in docstring
* Fix docstring and tests
* Adds RandomContrast and associated tests
* Remove arithmetic comment
* Adds RandomBrightness and tests
* Fix docstring and format
* Fix nits and add backend generator
* Inlines random_contrast helper
* Add bincount op
* Add CategoryEncoding layer and tests
* Fix formatting
* Fix JAX issues
* Fix JAX bincount
* Formatting and small fix
* Fix nits and docstrings
* Add args to bincount op test
