Broken links in documentation

[tkazec]

https://facebook.github.io/create-react-app/docs/advanced-configuration

You can adjust various development and production settings by setting environment variables in your shell or with .env.

.env links to https://facebook.github.io/docs/adding-development-environment-variables-in-env, which does not exist. I could not find any equivalent URL through Google.

---

https://facebook.github.io/create-react-app/docs/using-https-in-development

One particular case where this could be useful is when using the "proxy" feature to proxy requests to an API server when that API server is itself serving HTTPS.

the "proxy" feature links to https://facebook.github.io/docs/proxying-api-requests-in-development, which does not exist. I could not find any equivalent URL through Google.

[BuckyMaler]

It appears many, if not all, links to document files are broken. Absolute paths are used at this time, however Docusaurus recommends document linking differently.

New markdown files within docs will show up as pages on the website. Links to those documents are created first by using the id in the header of each document. If there is no id field, then the name of the file will serve as the link name.

For example, [.env](/docs/adding-development-environment-variables-in-env) in advanced-configuration.md should be [.env](adding-custom-environment-variables.md). As you can see I also included the updated filename. As noted above, the document's id can also be used, but since that's optional it may be a good convention to use the filename always.

@tkazec if you don't have time to submit a PR, I'd be happy to. I imagine this PR should update all broken document links.

[tkazec]

@BuckyMaler Wow thanks for the detailed explanation! Unfortunately I am in a huge time crunch at the moment (create-react-app is helping though!) and won't be able to fix this myself.

[BuckyMaler]

#5552 fixes this.