Release 2.9.0

• Add simple filtering if provided a minutes argument in clean_duplicate_history (gh-606)
• Add setting to convert FileField to CharField instead of TextField (gh-625)
• Added notes on BitBucket Pipelines (gh-627)
• import model ContentType in SimpleHistoryAdmin using django_apps.get_model
  to avoid possible AppRegistryNotReady exception (gh-630)
• Fix utils.update_change_reason when user specifies excluded_fields (gh-637)
• Changed how now is imported from timezone (timezone module is imported now) (gh-643)
• settings.SIMPLE_HISTORY_REVERT_DISABLED if True removes the Revert
  button from the history form for all historical models (gh-632))