Remove usage of HistoryManager and replace with simplistic Undo logic

bulk_reminders/undo.py

@@ -1,6 +1,6 @@
 import logging
 import os
-from typing import Iterator, List
+from typing import Any, Iterator, List
 
 import jsonpickle
 
@@ -68,6 +68,13 @@ class HistoryManager(object):
         self.stages.insert(0, newStage)
         self.save()
 
+    def verify(self, calendarID: str, known_events: List[Any]) -> None:
+        """Given a calendar ID and a list of events from this calendar, make sure there are no IDPairs in storage that no longer exist any more."""
+        pass
+
+    def collapse(self) -> None:
+        pass
+
 
 class Stage(object):
     def __init__(self, index: int, commonCalendar: str) -> None: