Reworded menu options for 2019 assignment.

sentiment.py

@@ -2,8 +2,8 @@ from enum import Enum
 
 
 class MenuOption(Enum):
-    SHOW_REVIEW = 'Show a review'
-    SAVE_TOKEN_LIST = 'Save the token list to a file'
+    SHOW_REVIEWS = 'Show reviews'
+    CHECK_TOKEN = 'Check if a token is present'
     SHOW_DOCUMENT_FREQUENCY = 'Show the document frequency for a particular token'
     SHOW_TOKEN_STATISTICS = 'Show all statistics for a particular token'
     SHOW_SENTENCE_STATISTICS = 'Show the statistics for a sentence'