add additional links to "see also" sections

- added extra references and references to existing articles

Author: andrewconnell

docs/spfx/sharepoint-2016-support.md

@@ -1,7 +1,7 @@
 ---
 title: SharePoint Framework development with SharePoint 2016 Feature Pack 2
 description: SharePoint Server 2016 Feature Pack 2 supports SharePoint Framework client-side web parts hosted in classic SharePoint pages.
-ms.date: 12/28/2021
+ms.date: 04/25/2022
 ms.localizationpriority: high
 ---
 # SharePoint Framework development with SharePoint Server 2016 Feature Pack 2
@@ -100,3 +100,4 @@ For more information, see [issue #1002](https://github.com/SharePoint/sp-dev-doc
 
 - [SharePoint Framework Overview](sharepoint-framework-overview.md)
 - [SharePoint Framework development tools and libraries compatibility](compatibility.md)
+- [Definitive guide for developers: SharePoint Framework for SharePoint Server 2016](https://www.voitanos.io/blog/definitive-guide-sharepoint-framework-sharepoint-server-2016/)

docs/spfx/sharepoint-2019-support.md

@@ -1,7 +1,7 @@
 ---
 title: SharePoint Framework development with SharePoint Server 2019 & SharePoint Server SE
 description: SharePoint Server 2019 supports SharePoint Framework client-side web parts in classic and modern pages, and extensions in modern pages.
-ms.date: 12/28/2021
+ms.date: 04/25/2022
 ms.localizationpriority: high
 ---
 # SharePoint Framework development with SharePoint Server 2019 & SharePoint Server SE
@@ -79,3 +79,5 @@ For more information, see [issue #1002](https://github.com/SharePoint/sp-dev-doc
 
 - [SharePoint Framework Overview](sharepoint-framework-overview.md)
 - [SharePoint Server 2019 development platform](../general-development/sharepoint-2019-development-platform.md)
+- [Definitive guide for developers: SharePoint Framework for SharePoint Server 2019](https://www.voitanos.io/blog/definitive-guide-sharepoint-framework-sharepoint-server-2019/)
+- [Definitive guide for developers: SharePoint Framework for SharePoint Server SE](https://www.voitanos.io/blog/definitive-guide-sharepoint-framework-sharepoint-server-subscription-edition/)

docs/spfx/sharepoint-framework-why.md

@@ -38,3 +38,7 @@ Historically, developers created web parts as full trust C# assemblies that were
 However, current development models usually involve JavaScript running in a browser making REST API calls to the SharePoint and Microsoft 365 back-end workloads. C# assemblies don’t work in this world. Developers needed a new development model.
 
 The SharePoint Framework is the next evolution in SharePoint development.
+
+## See Also
+
+- [Why did Microsoft create the SharePoint Framework (SPFx)?](https://www.voitanos.io/blog/spfx-5w1h-why-did-microsoft-create-sharepoint-framework/)