replace assert() with message logging

core/models/caves.py

@@ -1,7 +1,6 @@
 import string
 import os
 import datetime
-import logging
 import re
 import json
 from subprocess import call

core/models/troggle.py

@@ -1,7 +1,6 @@
 import string
 import os
 import datetime
-import logging
 import re
 import resource
 from subprocess import call
@@ -51,7 +50,7 @@ class DataIssue(TroggleModel):
     This is a use of the NOTIFICATION pattern: 
     https://martinfowler.com/eaaDev/Notification.html
     
-    And we need to use it to replace all assertions in the code too:
+    We have replaced all assertions in the code with messages and local fix-ups or skips:
     https://martinfowler.com/articles/replaceThrowWithNotification.html
     """
     date = models.DateTimeField(auto_now_add=True, blank=True)