Fp8 dyn per tok

[robertgshaw2-neuralmagic]

Redo of: #6547

SUMMARY:

• turns on dynamic per token quantization for fp8
• enables fallback if cutlass kernels are not supported
• add test cases

RESULTS:

nm-testing/Meta-Llama-3-8B-Instruct-W8A8-FP8-Channelwise-compressed-tensors

• GSM with dynamic per token:

|Tasks|Version|     Filter     |n-shot|  Metric   |   |Value|   |Stderr|
|-----|------:|----------------|-----:|-----------|---|----:|---|-----:|
|gsm8k|      3|flexible-extract|     5|exact_match|↑  |0.753|±  |0.0136|
|     |       |strict-match    |     5|exact_match|↑  |0.756|±  |0.0136|

• GSM with dynamic per tensor:

|Tasks|Version|     Filter     |n-shot|  Metric   |   |Value|   |Stderr|
|-----|------:|----------------|-----:|-----------|---|----:|---|-----:|
|gsm8k|      3|flexible-extract|     5|exact_match|↑  |0.748|±  |0.0137|
|     |       |strict-match    |     5|exact_match|↑  |0.747|±  |0.0138|

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