test base: handle app context
Merge pull request #59 from orvsd/base_test_app_context

test base: handle app context
Fixed serialization error for install_course task.
Merge pull request #62 from dean/fix-celery-hardcode

Fixed serialization error for install_course task.
courses: don't hardcode a version filter

refs #55
course install: remove site version restriction

refs #55
course install: filter out non 2.x sites

refs #55