Reviewed LogisticRegression

[Ce11an]

What does this PR do?

Reviewed LogisticRegression as part of #839

• Created protective methods to share code.
• Using nn.CrossEntropyLoss.
• Updated docstrings.
• Fixed previously stale issues Logging and progress bar values not detaching #793 and Trained regression model does not produce validation or test results #794.
• Using self.log: Use self.log and newest lightning API in all bolts models #405.

Still need to do the following before merging:

• Update tests
• Discuss the coupling between the Model and the accuracy metric.
• Discuss the coupling between the Model and the loss function.

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Did you have fun?

Of course 🥳

[Ce11an]

Hey all 👋🏻

If I could have an initial review that would be great 😄

Are we happy to keep accuracy within the class? Ideally, I don't want to couple it, so if you have any suggestions/examples of Lighting code that solves this issue?

Also, do you have any recommendations on how to properly unit-test sub-classes of LightningModule?

Thanks!!