added clarification on the newline token we model

examples/stories/README.md

@@ -8,7 +8,7 @@ The dataset can be downloaded like this:
 curl https://s3.amazonaws.com/fairseq-py/data/writingPrompts.tar.gz | tar xvzf -
 ```
 
-and contains a train, test, and valid split. The dataset is described here: https://arxiv.org/abs/1805.04833, where only the first 1000 words of each story are modeled. 
+and contains a train, test, and valid split. The dataset is described here: https://arxiv.org/abs/1805.04833. We model only the first 1000 words of each story, including one <newLine> token. 
 
 
 Example usage: