Show context for access mappings in event log
Merge remote-tracking branch 'origin/develop' into feature/event-log-role-mappings
Fix `context.related_object` assignments

* Now uses the same pattern as other polymorphic links instead of a
  special case
Migration to fix `related_object` links in Program contexts

* Previously these were not set correctly
Revert workaround for invalid `UserRole` log events
Merge pull request #1271 from reciprocity/feature/event-log-role-mappings

Show context for access mappings in event log