Update docs to reflect new requirements for Chocolatey CLI 2.0.0

- [ ] You are going to need to have .NET Framework 4.8 installed.
- [ ] Remove all mention of Web PI as an alternative source.
- [ ] Document the new `.chocolatey` folder and what it is used for.
- [ ] Remove mention of pre-1.0 CLI and pre-v5 versions from the `configuration.md` document listing CLI configuration items
- [ ] Update the install-directory-override.md, private-cdn.md, and virus-check.md document files as they contain Options and Switches fragments from the CLI help docs which will be updated during the release.
- [ ] Update the Chocolatey products dependencies to include v2.0.0 (note that we must also have 1.x as it is still supported).

Add other items that come up.