[Feat]: GitHub Support

[jdaniel-cpts]

Is your feature request related to a problem? Please describe.
Support for Github on Windows

Describe the solution you'd like
GVM support for GitHub on Windows OS. I've attached an updated version of the gvm file that includes additional lines necessary for the support. Wasn't sure if you would allow a pull request or not so please see file

Describe alternatives you've considered
Possibly using embedded linux on windows but Gitbash works and is a much lighter solution. We've been using it to develop golang for many years.

Additional context
Here is an output of gvm running against gitbash on windows using the attached version of the file. Notice its successfully downloading zip version of amd64

gvm.txt

[benjivesterby]

@jdaniel-cpts A PR would be great. Thank you for using gvm I haven't personally used it in Git bash so that's awesome!