Generate nuget package for CppSharp.Runtime (#1574)

build/build.sh

@@ -77,6 +77,11 @@ pack()
   find_msbuild
   $msbuild -t:restore "$rootdir/src/Package/CppSharp.Package.csproj" -p:Configuration=$configuration -p:Platform=$platform
   $msbuild -t:pack "$rootdir/src/Package/CppSharp.Package.csproj" -p:Configuration=$configuration -p:Platform=$platform -p:PackageOutputPath="$rootdir/artifacts"
+
+  if [ $oshost = "windows" -a $platform = "x64" ]; then
+    $msbuild -t:restore "$rootdir/src/Runtime/CppSharp.Runtime.csproj" -p:Configuration=$configuration -p:Platform=$platform
+    $msbuild -t:pack "$rootdir/src/Runtime/CppSharp.Runtime.csproj" -p:Configuration=$configuration -p:Platform=$platform -p:PackageOutputPath="$rootdir/artifacts"
+  fi
 }
 
 test()