* Added a `Guidance` method to `LLamaTokenDataArray` which applies classifier free guidance

* Factored out a safer `llama_sample_apply_guidance` method based on spans

* Created a guided sampling demo using the batched executor

* fixed comment, "classifier free" not "context free"

* Rebased onto master and fixed breakage due to changes in `BaseSamplingPipeline`

* Asking user for guidance weight

* Progress bar in batched fork demo

* Improved fork example (using tree display)

* Added proper disposal of resources in batched examples

* Added some more comments in BatchedExecutorGuidance