Provide a nodeIntegration option for webpack renderer config

[malept]

Preflight Checklist

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• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Problem Description

From #2289:

Target: web not working for renderer processes with nodeIntegration: true

While it's certainly debatable whether or not to have nodeIntegration active in the renderer processes, I can't fully swap Zettlr over to the new sandboxed models in an instance. The newly added target: ['web', 'electron-renderer'] throws errors because webpack won't leave require()s alone (this includes the index.js from the electron-package, which is being called whenever some node module is being required). The only way I have found to solve it is to overwrite the target of the renderer

Proposed Solution

Add a nodeIntegration option to WebpackPluginRendererConfig which sets the target appropriately:

• When nodeIntegration is true, the target is electron-renderer.
• When nodeIntegration is false, the target is web.

Defaults to false since Electron has defaulted nodeIntegration to false since Electron 5.

Alternatives Considered

Again, from #2289:

Manually set target: 'electron-renderer' for the renderer process

This puts the onus on the app developer to know about Webpack targets, and I'd prefer to avoid that.

Additional Information

This will probably also need documentation on the website.