Document URL feature in [ghq "https://git.example.com/repos/"]

[aubreypwd]

=== Example configuration (.gitconfig):

....
[ghq "https://git.example.com/repos/"]
vcs = git
root = ~/myproj
....

In the README you document this but I'm not sure what the URL https://git.example.com/repos/ means or does. I would love clarification, and I also think it could be documented a bit more afterwards to be clear how I can make good use of this.