Add upgrade guide to website

[Methuselah96]

No description provided.

[changeset-bot]

⚠️ No Changeset found

Latest commit: edc0ab5

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit edc0ab5:

Sandbox	Source
react-codesandboxer-example	Configuration

[Methuselah96]

Still working on v5 upgrade guide and TypeScript documentation.