[FMS-184] Add filter on security_level (public and private).
Merge branch 'master' of github.com:CIRB/django-fixmystreet

# By CIRB Jenkins
# Via CIRB Jenkins
* 'master' of github.com:CIRB/django-fixmystreet:
  Back to development: 3.0.1
  Preparing release 3.0.0