Update README.md (#204)

Author: natemcmaster

README.md

@@ -1,10 +1,8 @@
-HttpClient Factory
-===
+HttpClient Factory [Archived]
+=============================
 
-AppVeyor: [![AppVeyor](https://ci.appveyor.com/api/projects/status/github/aspnet/HttpClientFactory?branch=dev&svg=true)](https://ci.appveyor.com/project/aspnetci/HttpClientFactory/branch/dev)
-
-Travis:   [![Travis](https://travis-ci.org/aspnet/HttpClientFactory.svg?branch=dev)](https://travis-ci.org/aspnet/HttpClientFactory)
+**This GitHub project has been archived.** Ongoing development on this project can be found in <https://github.com/aspnet/Extensions>.
 
 Contains an opinionated factory for creating HttpClient instances.
 
-This project is part of ASP.NET Core. You can find samples, documentation and getting started instructions for ASP.NET Core at the [Home](https://github.com/aspnet/home) repo.
+This project is part of ASP.NET Core. You can find samples, documentation and getting started instructions for ASP.NET Core at the [AspNetCore](https://github.com/aspnet/AspNetCore) repo.