* Enable cross_entropy loss to handle dense targets
Dense targets means probabilities or one-hot encodings.
* better shape check of weights
* nits in docstring
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Co-authored-by: Awni Hannun <awni@apple.com>
* update module to check weights on load, also fix docs and reorganize tests
* nits + rebase
* a few more docs updates for Module
* use manual module file
* comment