detect win64 by user agent

[develar]

trafficstars

fix /download universal link (win64 artifact must be returned)

Test added, works in production.

[SamyPesse]

Thanks, please change the indentations of detectPlatformByUserAgent to use 4 spaces

[loprima-l]

Hi, I merged the project to a new repo to start maintain it, I would be glad if you can put your pull request here : https://github.com/loprima-l/nuts-2