Core: Multiple Inputs, Outputs, and Keyword Arguments

[chr5tphr]

• use additions to forward hooks in torch 2.0.0 to pass kwargs to pass keyword arguments
• handle multiple inputs and outputs in core.Hook and core.BasicHook, by passing all required grad_outputs and inputs to the backward implementation

TODO:

• finish draft and test implementation

• add tests

• add documentation

• This stands in conflict with #168, but promises a better implementation by handling inputs and outpus as common to a single function, rather than individually as proposed in #168

• This does not deal with parameter gradients, which are better left to a seperate PR

• This will implement #176