* Added support for Django 2.x.
* Added support for Python 3.
* Added individual report fields to `CSPReport` model to allow more fine-grained filtering of data.
* Added storage of the user agent with the report.
* Added Django `AppConfig` to properly register Django app.
* Added a Django management command to delete old `CSPReport` objects from the database.
* Added a Django management command to display a summary of recent reports.