[MERGE] workaround for bug #81689: give a proper error message instead of traceback when symlink cannot be created (e.g. on Windows)

[Aaron Bentley]

Aaron Bentley has voted resubmit.
Status is now: Resubmit
Comment:
Please add a test case as I described.

For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C47454C1D.2030807%40ukr.net%3E