Disable Karma unit tests, superseded by E2E tests

The Karma unit tests in Scriptureforge were only proof-of-concept tests
that didn't test anything useful, and the little bit of code they test
was completely covered by the Protractor E2E tests anyway. Since they
haven't been maintained to keep in touch with our changing APIs, and are
currently providing no value except for causing build failures, we'll
disable them.