Make muzzle generate helperClassNames() method

[mateuszrzeszutek]

First part of #1374

This PR contains the actual logic behind collecting & ordering helper class names, helperClassNames() methods are left untouched to avoid merge conflicts - I'll remove all those methods in a separate PR.

[trask]

❤️!!

This just bit me (yet again) 😭, I renamed a helper class and forgot to update the helperClassNames(): 2356d5b

I sent a PR to your branch with a couple of potential simplifications. Feel free to add feedback on my PR and we can discuss over there or over here.

[mateuszrzeszutek]

I sent a PR to your branch with a couple of potential simplifications. Feel free to add feedback on my PR and we can discuss over there or over here.

Nice! I love how it simplified the dependency cycle stuff.

I've added some minor stuff over that: one more unit test, removed getClassName() method that was not necessary.

[trask]

I sent a small commit directly to your branch to clarify my understanding of what the tests are testing, let me know if looks good

[mateuszrzeszutek]

I sent a small commit directly to your branch to clarify my understanding of what the tests are testing, let me know if looks good

👍 Thanks!

I've added one more assertion for the enum class:

    assertThatContainsInOrder helperClasses, [
      OtherTestHelperClasses.TestEnum.name,
      OtherTestHelperClasses.TestEnum.name + '$1',
    ]

[trask]

I've added one more assertion for the enum class

oh yes! I didn't notice that extends relationship 👍

[trask]

🎉🎉🎉