WIP: add webpack bundle analyzer

[themre]

Based on #798 I would like to propose to add some bundle analyzer into CRA. I would however like to put it into some conditional scripts or pass some arguments into build script, like: const addAnalyzer = process.argv.indexOf('--stats') !== -1;.

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[chrisprice]

@themre looks like it started up a server which it expected the user to terminate, as there was no user the build timed out.

[viankakrisna]

@themre judging from the docs here https://github.com/th0r/webpack-bundle-analyzer#installation-and-usage

  // Can be `server`, `static` or `disabled`.
  // In `server` mode analyzer will start HTTP server to show bundle report.
  // In `static` mode single HTML file with bundle report will be generated.
  // In `disabled` mode you can use this plugin to just generate Webpack Stats JSON file by setting `generateStatsFile` to `true`.
  analyzerMode: 'server',

maybe you can use

analyerMode: 'static'

?

[ro-savage]

An alternative would be using source-map-explorer. Its super simple to add, it doesn't auto-run as part of webpack instead you manually run when you want to see the bundle makeup, and its more generic and can be used in non-webpack projects.

Ninja edit: Looks like someone has add it with #1641 CRA only need sone of there two PRs as they both do the same thing.

[Timer]

I don't think we'll be merging this considering tools like source-map-explorer work and get the job done. Thanks!