Only report coverage for applications in projects by default
With django-discover-runner, which is the default test runner in Django 1.6+, only the tests in the project are tested, instead of testing all applications. django-coverage, however, returns coverage reports for every application installed except for those in COVERAGE_MODULE_EXCLUDES.
I don't care about third party application coverage, but filtering it out requires either:
adding each and every third party application to COVERAGE_MODULE_EXCLUDES, which is a major pain
making the module introspection tool respect COVERAGE_PATH_EXCLUDES so I can filter out all libraries in my virtualenv.
django-coverage following discover-runner's lead and only performing coverage reports on code in the project.