update tutorial.rst
update tutorial.rst

I hope the tutorial gets clearer now. There is still room for improvement, especially regarding how to prepare the training data. For non-programmers, rasa-nlu-trainer is a good choice; for informaticiens, since there are no scripts of generating, analyzing, merging training data provided by rasa-NLU (at least i don't find any and they are not mentionned in the docs), they need to create these scripts if they want to deal with more data.
RasaHQ/rasa_nlu,RasaHQ/rasa_nlu,RasaHQ/rasa_nlu