Simplify variables: step, epoch, max_epochs, min_epochs

[elliotwaite]

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• Did you write any new necessary tests?

What does this PR do?

Fixes #584.

PR review

Anyone in the community is free to review the PR once the tests have passed.
If we didn't discuss your PR in Github issues there's a high chance it will not be merged.

[Borda]

it is hard to see from the changes it it was changed everywhere, but otherwise it LGTM :]

[awaelchli]

It was not changed here for example.

[elliotwaite]

It was not changed here for example.

This change only addressed changing all max_num_epochs to max_epochs. Perhaps @Borda can help us out here, he worked on a previous change (#567) that addressed the switch from max_nb_epochs to max_num_epochs while preserving backward compatibility.

@Borda, any suggestions?

[Borda]

it should be change there too and propagate the change across system...
for back compatibility, add a property with the max_nb_epochs and dedicated warning

@poperty
def max_nb_epochs(self):
    """
    .. warning:: Deprecated... will be removed...
    """
    warn("Depredated... will be removed...", DeprecationWarning)
    return self.max_epochs

@elliotwaite @awaelchli willing to prepare follow-up PR?

[elliotwaite]

Thanks, @Borda. Created a PR: #613