Merge branch 'cleanup_libraries' into 'django3_migration'

beat/web/libraries/__init__.py

beat/web/libraries/admin.py

beat/web/libraries/api.py

beat/web/libraries/apps.py

beat/web/libraries/migrations/0001_initial.py

beat/web/libraries/migrations/0002_cxx_backend.py

beat/web/libraries/migrations/0003_auto_20161123_1218.py

beat/web/libraries/models.py

beat/web/libraries/serializers.py

beat/web/libraries/templates/libraries/list.html

beat/web/libraries/templates/libraries/panels/actions.html

beat/web/libraries/templates/libraries/panels/editor.html

beat/web/libraries/templates/libraries/panels/sharing.html

beat/web/libraries/templates/libraries/panels/table.html

beat/web/libraries/templatetags/library_tags.py

beat/web/libraries/tests/core.py

beat/web/libraries/tests/tests_api.py

beat/web/libraries/tests/tests_team.py

beat/web/libraries/tests/tests_user.py

beat/web/libraries/views.py