Regnet model

[mobley-trent]

This is a PR for the implementation of RegNet into the ivy model zoo

[juliagsy]

Hey! Not sure if it's ready for a review yet, but just thought I'd leave some comments while I'm going through the PRs. Ivy layers have some small differences in terms of kwargs naming as well as the type of kwargs available, the tests are erroring out at the moment so please do double check all tests! Thanks!

[juliagsy]

Hey! Just a quick one, I'm getting this error when checking it, I'm guessing the class is not preperly initialised when in use, could you please double check the BlockParams part? Thanks!

ivy_models_tests/regnet/test_regnet.py:15: in <module>
    model = VARIANTS[model_var](pretrained=load_weights)
ivy_models/regnet/regnet.py:153: in regnet_y_400mf
    model = RegNet(BlockParams, num_classes, stem_width)
ivy_models/regnet/regnet.py:66: in __init__
    super(RegNet, self).__init__(v=v)
ivy_models/base/model.py:17: in __init__
    super(BaseModel, self).__init__(*args, **kwargs)
/opt/miniconda/envs/multienv/lib/python3.10/site-packages/ivy/stateful/module.py:174: in __init__
    self.build(*args, dynamic_backend=dynamic_backend, **kwargs)
/opt/miniconda/envs/multienv/lib/python3.10/site-packages/ivy/stateful/module.py:666: in build
    built = ivy.default(self._build(*args, **kwargs), True)
ivy_models/regnet/regnet.py:96: in _build
    self.block_params.widths,
E   AttributeError: type object 'BlockParams' has no attribute 'widths'