Expect case normalized words

Ruby, Elixir, Clojure, and others expect words to be normalized in
some way so that "Go", "go", "GO" are not considered different words.

Author: wobh

word-count/example.py

@@ -5,4 +5,4 @@ def word_count(text):
     """Return a Counter object that maps from the words contained in
     the phrase to their respective counts
     """
-    return Counter(text.split())
+    return Counter(text.lower().split())

word-count/word_count_test.py

@@ -36,8 +36,8 @@ def test_include_numbers(self):
 
     def test_mixed_case(self):
         self.assertEqual(
-            {'go': 1, 'Go': 1, 'GO': 1},
-            word_count('go Go GO')
+            [3],
+            list(word_count('go Go GO').values())
         )
 
     def test_multiple_spaces(self):