allow to generate only exports for css in node

[sokra]

add more options to the DeterministicModuleIdsPlugin to allow to opt-in into a fixed mode

optimize module iterations for module id assignment

What kind of change does this PR introduce?
feature

Did you add tests for your changes?
yes

Does this PR introduce a breaking change?
no

What needs to be documented once your changes are merged?
nothing

[webpack-bot]

For maintainers only:

• This needs to be documented (issue in webpack/webpack.js.org will be filed when merged)
• This needs to be backported to webpack 4 (issue will be created when merged)

[vankop]

So this should allowing to kind of map module name to id ? e.g.

{
    "C:\\Users\\a\\repo\\a.css|classname_aa": "1",
    "C:\\Users\\a\\repo\\b.css|classname_aa": "2",
}

[sokra]

Yep. Here you need to use it to sync the modules ids between Client and Server compiler so CSS Modules generate the same class names in both.

CSS Module class names are based on module ids in the new implementation.

[sokra]

Example of the file:

{"./style.module.css":1876,"./style2.module.css":1054}