Move js-beautify and html-minifier to cli

[TrySound]

Ref #1947

• minify outlook conditionals unconditionally like merging
• moved js-beautify and html-minifier to cli
• deprecated "minify" and "beautify" options in mjml-core

[TrySound]

сс @kmcb777 @iRyusa @DRoet

[iRyusa]

Looks good to me cc @ngarnier 5.X branch will remove those from core maybe we should discuss if we have more breaking changes to push in it ?

[ngarnier]

Ok yeah @iRyusa let's chat this week

[iRyusa]

We've just discussed about this @TrySound and we're ok to remove both of them in MJML5. However we still want to provide somekind of "easy" way to get them back. I think it could be done with .mjmlconfig where you can list postRender hooks and register functions + arguments ?

{
  postRender: { "packageName": [{ options}, anotherArgs, anotherArgs] }
}

I'm not sure about the format tho, and if dynamic require would be an issue with browser build (webpack/rollup/...).

Can we discuss about this together so we can ease the transition in MJML5 with proper doc on that ?

[TrySound]

I think we can provide custom plugins with hooks which run any minification or other tool. I can implement it in separate PR and default to it in cli.

[iRyusa]

That would be so cool 👍 I'm merging this one as it's fine for MJML 4.8 then

[TrySound]

Will do this in a couple of weeks after vacation.

[IanEdington]

@TrySound It seems like this will this break minification in the gulp tool. Is that true?

[iRyusa]

Nope it wont the option will still be handled in core but display a warning during the transition. We'll just add those into gulp-mjml dependencies that's not that hard

[TrySound]

Or piped gulp plugins can be used instead to not bloat gulp-mjml and make it single purpose.

[IanEdington]

@iRyusa Thanks for pointing that out 👍

@TrySound I like the idea of simplifying MJML by removing these dependencies. That approach seems like a good one for a v5 change.