Add pytorch LUT quantizers an option to be exported in ONNX.
Change LUT quantizers API to receive lists instead of np arrays (for lut values and thresholds).
Adapt all LUT tests that pass np arrays to lists.
Fix the issue with ignoring the channel axis in LUT quantizers (and tests that assumed the channel axis is always 0)
Add pytorch LUT quantizers an option to be exported in ONNX. Change LUT quantizers API to receive lists instead of np arrays (for lut values and thresholds). Adapt all LUT tests that pass np arrays to lists. Fix the issue with ignoring the channel axis in LUT quantizers (and tests that assumed the channel axis is always 0)