Clean up package.json files in the `examples` directory:
- Add `private: true`
- Remove `version` (because they are irrelevant for packages that are not meant to be published)
- Remove `name` (because they are optional for packages that are not meant to be published, and when someone clones an example, they often rename it and the property becomes stale)
- Remove `author`
- Remove `description`
- Remove `license`
Also remove `with-dynamic-app-layout` example completely, since it does the same as `layout-component` (https://github.com/vercel/next.js/pull/27121#discussion_r668178408).
## Documentation / Examples
- [x] Make sure the linting passes
[With next 11 requiring react 17](https://nextjs.org/blog/next-11#upgrade-guide), most of the examples
need to be updated, so the following snippet updated all the examples to
a compatible react version.
```bash
cd examples/
fd -g 'package.json' | xargs sed -r -i 's/"react": ".*"/"react": "^17.0.2"/
fd -g 'package.json' | xargs sed -r -i 's/"react-dom": ".*"/"react-dom": "^17.0.2"/'
# exclude experimental react version
git checkout with-reason-relay/package.json
```
I realized while looking over this that the `autoprefixer` plugin isn't being used by postcss because it's not included in the `postcss.config.js`. Additionally, since `postcss-preset-env` doesn't support PostCSS 8 yet, and it includes PostCSS 7 as a dependency, I've removed that package.
There is an open issue to add PostCSS 8 support to `postcss-preset-env` [here](https://github.com/csstools/postcss-preset-env/issues/191). @kripod's comments on my other PR #20956 are what prompted me to check this out.
On a side note, it looks like all the CMS examples use Tailwind CSS v1 still, so that's something someone (possibly myself) could tackle later.
[ch2502]
- Added new import flow to every CMS example, using the deploy button, and removed `vercel.json`
- Replaced `dotenv` with the new env support in outdated examples
* TakeShape Example
* Fix preview logic
* Update README
* Fix broken link
* Be more clear with the relationship field
* Use latest next.js for cms examples
* Only show enabled items
* Ignore current slug
* Fix queries
* Add takeshape demo
* Added link to blog-starter
Co-authored-by: Luis Alvarez D <luis@zeit.co>
