extensions/Directory.Build.targets (5 lines of code) (raw):
<Project>
<Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory)../, $(_DirectoryBuildTargetsFile)))/$(_DirectoryBuildTargetsFile)"
Condition=" '$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory)../, $(_DirectoryBuildTargetsFile)))' != '' " />
<Import Project="$(TargetsRoot)WorkerExtensions.targets" />
</Project>