[planning] Repository design and planning

The content this repo hosts is product documentation related to WPF and WinForms. This content is currently hosted in [dotnet/docs](https://github.com/dotnet/docs) repo and is really focused on .NET Framework. With WPF and WinForms going open source and those versions targeting .NET Core/5+ (further referred to as simply ".NET"), the .NET Framework content will be copied and updated. This means that the repo will be designed to host versioned content with the major separator being .NET Framework and .NET.

### Versioning

The version monikers will be:

- .NET Framework 4.x
- .NET 5 / .NET Core 3.1

The `framework` folder will be versioned at `.NET Framework 4.x` and the `net` folder will be versioned with `.NET 5`.

### Folder structure

The content will be structured as follows:

- root
- framework
- wpf
- winforms
- shared
- net
- wpf
- winforms
- shared

The `framework` folder represents the content migrated from the dotnet/docs repos for both WPF and WinForms. The `net` folder represents the `.NET 5+/.NET Core 3.1`

The `shared` folders represent articles shared across wpf and winforms. For example, creating an MSIX package will probably be the same for both .NET 5 WPF and .NET 5 WinForms apps.

### Tasks

#### Repo specific

- [x] Create labels (ported from dotnet/docs)
- [x] New issue templates
- [x] License for .NET Foundation
- [x] Setup auto labeler
- [ ] Readme update
- [x] Add whats-new system
- [x] Convert root page to hub
- [ ] Setup loc
- [ ] Add rules for xaml-services in ghal

#### Initial publish winforms

- [x] Move framework winforms content (#4)
- [x] Create breadcrumbs (#15)
- [x] Create placeholder .net 5 winforms content (#16)
- [x] Merge working branch of .net 5 winforms content into master
- [x] Update metadata (#16)
- [x] Landing pages (#16) (more)
- [x] Update links in dotnet hub pages
- [x] Merge delete/redirects of dotnet/docs content (dotnet/docs#20279)
- [x] Publish (#96)

#### Winforms

- [ ] Move winform content planning issues from dotnet/docs here
- [ ] Determine if we'll publish some of the content had add "Preview content" banners
- [ ] Clean up dotnet/docs repo links in existing files (ensure local links are changed and don't rely on redirects)
- [ ] Clean up api ref links

#### Initial publish WPF

- [x] Move framework WPF content (#17)
- [x] Create breadcrumbs (#17)
- [x] Landing pages
- [x] Update links in dotnet hub pages (dotnet/docs#20445)
- [x] Merge delete/redirects of dotnet/docs content (dotnet/docs#20445)
- [x] Publish

#### WPF

- [x] Move old desktop-guide wpf content as .NET 5 (dotnet/docs#20678)
- [ ] File issues for new WPF content plan
- [x] Move XAML-SERVICES content (dotnet/docs#20678)
- [ ] Clean up dotnet/docs repo links in existing files (ensure local links are changed and don't rely on redirects)
- [ ] Clean up api ref links