fixup! fixed asset search query. moved location_to_son to LocationBase.py.
Fix cohort.course_id naming
Clean up how courses are iterated on instructor dashboard
Fix syntax error
Make dashboard.tests a python module
Merge remote-tracking branch 'edx/opaque-keys-validate' into opaque-keys
Merge remote-tracking branch 'edx/opaque-keys-location-to-son' into opaque-keys
Merge remote-tracking branch 'origin/opaque-keys-test-fixes' into opaque-keys