New test for CShellLink:SetPath and GetPath

This Patch implements a few test for CShellLink::SetPath / GetPath. It detects a few cases where the implementation in ROS need some love.

E.g. it tests setting pathes by system-variables (e.g. %comspec%). The current implementation in ROS differs from Win 2003. ROS trys to expand this variable to a "full" path. So you get "c:%comspec%" or simliar. In Windows you get "%comspec%".