Directory.Build.targets

<Project>
  <PropertyGroup>
    <IsPackable>false</IsPackable>
  </PropertyGroup>
  <PropertyGroup Condition="'$(NuspecFile)' != ''">
    <IsPackable>true</IsPackable>
    <NuspecProperties>
      id=$(PackageId);
      version=$(ShortVersion)$(VersionSuffix);
      company=$(Company);
      copyright=$(Copyright);
      commitid=$(CommitID);
    </NuspecProperties>
  </PropertyGroup>
</Project>