handle the following issue

automl#1373 (comment)

this commit fixes the first 3 bullet points on the to do list.

1. rename hyperparameter "ngram_range" --> "ngram_upper_bound"
   this includes changing all *csv and *json files

2. Create a new textpreprocessing example_text_preprocessing.py, this new example features the 20Newsgroups dataset

import in example_text_preprocessing.py to long, but i can not come up with a good solution

include feedback from 02.24.

Author: Louquinze

examples/40_advanced/example_text_preprocessing.py

@@ -80,13 +80,13 @@
 # View the models found by auto-sklearn
 # =====================================
 
-print(automl.leaderboard())
+# print(automl.leaderboard())
 
 ############################################################################
 # Print the final ensemble constructed by auto-sklearn
 # ====================================================
 
-pprint(automl.show_models(), indent=4)
+# pprint(automl.show_models(), indent=4)
 
 ###########################################################################
 # Get the Score of the final ensemble