Update setup.py

[GarethWright]

#GW - Add Windows Symlink support...requires elevated CMD / Powershell Prompt

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[GarethWright]

I signed it!

[googlebot]

CLAs look good, thanks!

[SeanHayes]

Closed & reopened to run new CI check.

[SeanHayes]

@GarethWright Do you know of any free services similar to Travis CI that will run in a Windows env?