* Added missing code in exemplary notebook - custom datasets fine-tuning
Added missing code in tokenize_and_align_labels function in the exemplary notebook on custom datasets - token classification.
The missing code concerns adding labels for all but first token in a single word.
The added code was taken directly from huggingface official example - this [colab notebook](https://github.com/huggingface/notebooks/blob/master/transformers_doc/custom_datasets.ipynb).
* Changes requested in the review - keep the code as simple as possible
e79a0faeae