(#204) Use external class for constants in the School model.
(#204) Bootstrap GenderConstants from Python to JS.
(#204) Bootstrap GenderConstants from Python to JS.

Resolves #204.
#169 Unit test for CurrentUserStore.
#169 CurrentUserStore unit test for testing deleting the reference to global.currentUser.
#169 Cleaned up more from previous commit.
#169 CurrentUserStore is subsribing to the dispatcher.
#169 logging in and out tests.