Revert "Fixed a small path separator bug in the topological_order module that occurs only on Windows."
Revert "Fixed a small path separator bug in the topological_order module that occurs only on Windows."

This reverts commit ead502518e618a2e01f033890af0b487625214e9.

asmodehn/catkin,wkentaro/catkin,shyamalschandra/catkin,thaddeustaylor/catkin,harmishhk/catkin,scpeters/catkin,shyamalschandra/catkin,ros/catkin,beni55/catkin,ros/catkin,meyerj/catkin,wkentaro/catkin,beni55/catkin,meyerj/catkin,harmishhk/catkin,scpeters/catkin,meyerj/catkin,jack-oquin/catkin,thaddeustaylor/catkin,jack-oquin/catkin,harmishhk/catkin,asmodehn/catkin,ros/catkin,beni55/catkin,asmodehn/catkin,wkentaro/catkin,scpeters/catkin,thaddeustaylor/catkin,jack-oquin/catkin,shyamalschandra/catkin