train : get raw text instead of page with html (#1905)

We probably want to train using just the text of Shakespeare instead of the html of the page displaying his work.

examples/train-text-from-scratch/README.md

@@ -4,7 +4,7 @@ Basic usage instructions:
 
 ```bash
 # get training data
-wget https://github.com/brunoklein99/deep-learning-notes/blob/master/shakespeare.txt
+wget https://raw.githubusercontent.com/brunoklein99/deep-learning-notes/master/shakespeare.txt
 
 # train
 ./bin/train-text-from-scratch \