[utils] Adjust logic in clear-container-cache. factoryCache -> factoryManagerCache

[alexhancock]

This change should fix things related to #48 for now, at least based on testing I have done with a vanilla CLI app.

We should all organize and have a discussion about the future of Ember's component and component manager interfaces so that eventually this addon can rely on public APIs instead of private ones. cc @toranb @MiguelMadero

See comments here for more on this topic.

Also: emberjs/ember.js#15057

[alexhancock]

Looks like the tests have failed. Is there a good way I can run them locally to fix things up?

[toranb]

@alexhancock I've thrown up another PR that solves this build issue for everything except ember 1.13 (ember-try issue atm). Asked @MiguelMadero to give it a look before we merge tomorrow

[toranb]

@alexhancock huge huge thank you! Not sure why I never tried the cache factory clear like you did here! So thankful for your time and involvement today! I'll likely close out this PR (if that's cool w/ you) and ask that either you take credit in PR #52 or re-do that PR (after we make a decision on the ember 1.13 ember-try config). I'm not looking for credit/glory here but do think we need that ember-cli upgrade

Just let me know how you want to proceed later in the week

[alexhancock]

@toranb No problem! Happy to just close this one in favor of that! In terms of credit, maybe you could just @ mention me in the commit message for b53977c, but anything is fine really.

I will keep an eye on that change to see what the fix for the ENV issues ends up being.

Thanks!

[alexhancock]

Closing in favor of #52