What should happen when failure to load a module?

Currently, when requiring a test file, if an error gets throw, the error is logged by `console.error()` and the test-loader will continue to require the next test file.
See https://github.com/ember-cli/ember-cli-test-loader/blob/master/addon-test-support/index.js#L71

This effectively ignores all the tests that are part of the test file that did not get required, which would cause unexpected missing test coverage.

Was interested in knowing what is the rational in the choice of the current implementation.
@rwjblue would you have some context on this?