Fixing missing arguments for TransfoXL tokenizer when using TextGenerationPipeline (#5465)
Fixing missing arguments for TransfoXL tokenizer when using TextGenerationPipeline (#5465)

* overriding _parse_and_tokenize in `TextGenerationPipeine` to allow for TransfoXl tokenizer arguments
huggingface/transformers,huggingface/transformers,huggingface/pytorch-transformers,huggingface/transformers,huggingface/transformers