Adding .nuspec file

Author: ShawnLaMountain

src/ThunderDesign.Net-PCL.nuspec.in

@@ -0,0 +1,22 @@
+<?xml version="1.0"?>
+<package>
+  <metadata>
+    <id>${{ env.FILE_NAME }}</id>
+    <version>$version$</version>
+    <title>${{ env.TITLE }}</title>
+    <authors>ThunderDesign</authors>
+    <owners>ThunderDesign</owners>
+    <requireLicenseAcceptance>false</requireLicenseAcceptance>
+    <license type="expression">MIT</license>
+    <projectUrl>${{ env.GITHUB_URL }}</projectUrl>
+    <description>${{ env.DESCRIPTION }}</description>
+    <releaseNotes>See ${{ env.REPOSITORY_URL }}/releases/tag/$version$</releaseNotes>
+    <tags>${{ env.TAGS }}</tags>
+    <repository type="git" url="${{ env.REPOSITORY_URL }}" />
+  </metadata>
+  <files>
+    <!-- Example: adjust for your actual output paths/frameworks -->
+    <file src="src/ThunderDesign.Net-PCL.Threading/bin/Release/netstandard2.0/ThunderDesign.Net-PCL.Threading.dll" target="lib/netstandard2.0/" />
+    <file src="src/ThunderDesign.Net-PCL.SourceGenerators/bin/Release/netstandard2.0/ThunderDesign.Net-PCL.SourceGenerators.dll" target="analyzers/dotnet/cs/" />
+  </files>
+</package>