Update Webpack to v4.

[jaydenseric]

Fixes #41:

• Updated Webpack dependency to v4.0.0-beta.2.
• Updated Webpack related dependencies for the Yarn lock file.
• In the changelog fixed capitalization of “Webpack” everywhere and ran Prettier.

[jaydenseric]

Tested it using npm link, and it seems ok:

The warning is harmless, some packages are waiting for a stable v4 before adopting the new API and Webpack will still support the old for a while.

I looked into all the Webpack related dependencies and I could not find anything that would break moving to v4.

[ai]

@jaydenseric do you have this warning without --why?

[jaydenseric]

Yes.

[ai]

Could you please revert ChangeLog changes? ;) If you want to change format, it should be in the different PR.

[jaydenseric]

The changelog formatting matches the same way you have the readme formatted; new lines under headings.

[ai]

1. The warning should be from WebpackBundleAnalyzer. It is an only plugin added on --why.
2. In README.md I also have double new lines at the end of a section. I am not sure that we should copy this format to ChangeLog. Format purposes are different.

[ai]

Seems like you also need to fix tests, Webpack 4 changes sizes and WEBPACK_EMPTY_PROJECT

[jaydenseric]

Feel free to add commits to get this PR across the line, I don't have this project open anymore and am too busy ATM to work out the tests and things to see it through 🙂

[ai]

@jaydenseric don’t worry. I will finish it over the weekend. Can I only ask you to revert ChangeLog changes, because if I accept this PR (to fix tests), git history will be tricky?

[ai]

I created issue about depreacted warning:

webpack-contrib/webpack-bundle-analyzer#154

Also I should think on weekends about using Webpack’s mode instead of manually set UglifyJS.

[ai]

I made a PR to Webpack Bundle Analyzer. Since warning is showing in any Size Limit mode, I need to wait for this PR (or Size Limit tests will fail).

[ai]

PR to uglify-webpack-plugin was sent too webpack-contrib/uglifyjs-webpack-plugin#238

[ai]

PR to compression-webpack-plugin was sent too webpack-contrib/compression-webpack-plugin#100

[ai]

All PRs were accepted. I manually took changes from this commit aca11bf

[ai]

Released in 0.15.