Deprecate Some Packages

[avivkeller]

I propose the following:

1. @webpack-cli/configtest, @webpack-cli/info, @webpack-cli/serve deprecated, and moved into webpack-cli directly. These packages were never meant for users, and are installed with webpack-cli and IMO they don't need to be seperate packages.

2. create-new-webpack-app deprecated: A claim for create-webpack-app submitted, we take create-webpack-app, and re-released a version of create-webpack-app.

I'd gladly take on this, and any needed prereqs

[Lonewolfpup]

Thank you 🙏

[avivkeller]

(For an update, I'm working on this + simplifying webpack-cli.ts with some Commander logic (i.e. removing the custom help, etc)

[alexander-akait]

Close in favor of webpack/tsc#101, union already completed