tsort command might not be available on all OS.

After a bit more testing on windows, a couple of issues popped up. The tsort command was unknown, and the path definition for dep-concat from the Gruntfile have to be converted as well. Anyways, this is now working on windows for real :)

S: would be cool if, after you accept the pull request, you could update the npm module as well.

Thanks,
-Stephan