Allow to disable every configurator

[marmichalski]

Howdy, @nicolas-grekas.
As suggested, here comes a basic PR allowing to disable configurators. I am opening this in a current state to see if this approach is valid and to happily work on your feedback 😅.

Closes #881.

[lzakrzewski]

LGTM, thanks for addressing this 👍

[nicolas-grekas]

I didn't expect this approach. I don't think it makes sense to disable configurators case by case as that's going to provide broken experiences, where only part of a recipe is applied. Docker support is a bit special since that's not about the app itself.

Instead, I was expecting a single flag to disable all recipes.

(Note that this can already be achieved without patching flex by creating a recipe repo that ships no recipes.)

[marmichalski]

I didn't expect this approach. I don't think it makes sense to disable configurators case by case as that's going to provide broken experiences, where only part of a recipe is applied. Docker support is a bit special since that's not about the app itself.

Okay 😢

Instead, I was expecting a single flag to disable all recipes.

Sure, I'll change this PR into single-flag-to-rule-them-all then, thanks.

[maxhelias]

I don't see the added value even to disable all the recipes