Remove exemplar/project urls from course schema (#558)
Remove exemplar/project urls from course schema (#558)

These have been moved to level schema
codecombat/codecombat,javatlacati/codecombat,codecombat/codecombat,codecombat/codecombat,codecombat/codecombat,javatlacati/codecombat,javatlacati/codecombat,javatlacati/codecombat,codecombat/codecombat,javatlacati/codecombat