Added CCXCon app

cms/djangoapps/models/settings/course_metadata.py

cms/envs/aws.py

cms/envs/test.py

cms/envs/yaml_config.py

common/lib/xmodule/xmodule/course_module.py

lms/envs/aws.py

lms/envs/test.py

lms/envs/yaml_config.py

openedx/core/djangoapps/ccxcon/__init__.py

openedx/core/djangoapps/ccxcon/admin.py

openedx/core/djangoapps/ccxcon/api.py

...djangoapps/ccxcon/migrations/0001_initial_ccxcon_model.py

openedx/core/djangoapps/ccxcon/migrations/__init__.py

openedx/core/djangoapps/ccxcon/models.py

openedx/core/djangoapps/ccxcon/signals.py

openedx/core/djangoapps/ccxcon/tasks.py

openedx/core/djangoapps/ccxcon/tests/__init__.py

openedx/core/djangoapps/ccxcon/tests/factories.py

openedx/core/djangoapps/ccxcon/tests/test_api.py

openedx/core/djangoapps/ccxcon/tests/test_signals.py