timm.models: explicitly export attributes

[adamjstewart]

Same as #2399 but for timm.models. I didn't bother with any other __init__.py or star imports because I'm not currently using them.

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[rwightman]

@adamjstewart question, the from .model import * that rely on the __all__ within each model module, they don't trigger any mypy complaints?

[adamjstewart]

Star imports in general don't work with any static type checkers or style tools. In this case, it looks like mypy ignores star imports because it can't know whether or not something is defined. The following doesn't raise any complaints in mypy:

from timm.models import ResNet