Enable Multi-Unit Inputs For Numerical And Categorical Calibrators

[brianpark0126]

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About:

Add multi-unit capabilities to numerical and categorical calibration layers.

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Is your feature request related to a problem? Please describe.
As we build up the PyTorch Lattice Library, we will be implementing optimizations for the basic Lattice model which will require it to handle multiple units (RTL and Kronecker factored lattices). As a prerequisite, we will need the calibrators to accept multi-unit inputs.

Describe the solution you'd like
A refactoring of categorical_calibrator and numerical_calibrator classes to include multi unit functionality.

Describe alternatives you've considered
N/A

Additional context
N/A