Added NuGet Badge

Author: ShawnLaMountain

README.md

@@ -1,5 +1,6 @@
 # ThunderDesign.Net-PCL.Threading
 [![CI](https://github.com/ThunderDesign/ThunderDesign.Net-PCL.Threading/actions/workflows/CI.yml/badge.svg)](https://github.com/ThunderDesign/ThunderDesign.Net-PCL.Threading/actions/workflows/CI.yml)
 [![CD](https://github.com/ThunderDesign/ThunderDesign.Net-PCL.Threading/actions/workflows/CD.yml/badge.svg)](https://github.com/ThunderDesign/ThunderDesign.Net-PCL.Threading/actions/workflows/CD.yml)
+[![NuGet](https://img.shields.io/badge/nuget-v1.0.0-blue)](https://www.nuget.org/packages/ThunderDesign.Net-PCL.Threading/1.0.0)
 
 Thread-Safe Objects