Provide an option to install right click menu option for Windows

[lyc8503]

This implements #745.

Implemented two options for installing and uninstalling the Windows context menu and tested them on Windows.

By the way, I've also added a hint to upgrade pip and setuptools in the documentation (PEP660 has only been implemented in newer versions of setuptools)

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[mr-tz]

This looks great. I will test it next week and let you know if there's any other changes needed. Thank you very much!

[mr-tz]

Awesome, thank you very much. I like this solution and if people have issues given the various installation methods, we can fix this.

Only thing left to do is a small entry in the documentation at https://github.com/mandiant/flare-floss/blob/master/doc/usage.md. Can you add this, please?

[lyc8503]

Hi, I have updated the document, and thanks for your code review and feedback too. 😃

[mr-tz]

great work, thanks a lot!