make_sampler creates sampler chain with all sampling parameters

[neilmehta24]

Closes #1219

Apply samplers in this order: top-k --> top-p --> min-p --> temp

The sampler methods were refactored to return the transformed logits instead of a token. Now, we can can chain them together to apply a series of sampling methods.

The method names of the samplers were changed to indicate that the implementation has changed, i.e., each method returns logits instead of a token. I am not sure about the API stability requirements, so let me know if you have a preference on the method name.

The temperature adjustment was removed from each sampler application, and instead it's applied only once as the very last step.