DLL build proposal

[jodator]

Suggested merge commit message (convention)

Feature: Introduce the CKEditor 5 DLL build. Closes #8517.

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Additional information

WIP for now.

[jodator]

Things to open this PR to review:

• add image plugin to sample
• fix errors (or check if those will get fixed by @pomek's work in Implement the CKEditor5 global object based off the CKEditor5 DLLs #8521.

[pomek]

I don't want to be the person who will update 50 different webpack.config.js files if something should be changed :D

Let's extract the common part to a factory function (https://github.com/ckeditor/ckeditor5-dev/blob/i/8521/packages/ckeditor5-dev-utils/lib/builds/getpluginwebpackconfig.js) and modify the output via options (https://github.com/ckeditor/ckeditor5/blob/i/8521/packages/ckeditor5-html-embed/webpack.config.js).

[jodator]

@pomek that's a sound idea :) Let's have done during review. For now I'm trying to get green CI to have a starting point.

[jodator]

I'm waiting for the CI to validate that everything runs smoothly. The last piece is to add a build script for all the DLLs. I would push it now, but Travis still builds... 🤷‍♂️

[jodator]

🟢 🎉