Add a link to the getting started guide in README (#1722)

Author: rbenegal

README.md

@@ -15,7 +15,7 @@ This extension adds language support for Swift to Visual Studio Code, providing
 
 # Documentation
 
-The official documentation for this extension is [available on swift.org](https://docs.swift.org/vscode/documentation/userdocs).
+The [getting started guide](https://www.swift.org/documentation/articles/getting-started-with-vscode-swift.html) and [official documentation](https://docs.swift.org/vscode/documentation/userdocs) for this extension are available on [swift.org](https://www.swift.org).
 
 This extension uses [SourceKit LSP](https://github.com/apple/sourcekit-lsp) for the [language server](https://microsoft.github.io/language-server-protocol/overviews/lsp/overview/), which powers code completion. It also has a dependency on the [LLDB DAP](https://marketplace.visualstudio.com/items?itemName=llvm-vs-code-extensions.lldb-dap) extension to enable debugging.