- new setting to enable user exports defaults to False
- add setting to enable and disable user exports
- do not allow user exports when using s3 storage
- do not serve non-image files from /images/ (requires update to nginx settings)
- increase default file upload limit to 100MB to enable user exports to be imported (can be changed in .env)
- makes user_import_time_limit a site setting rather than a value in settings.py (note this applies to exports as well as imports)
- admins can change user_import_time_limit from UI
- admins can cancel stuck user imports
- disabling new imports also disables user imports