Configure the git user based on the host machine

[becw]

It would be great if we could set the git user.name and user.email based on the user's host, so that commits made within the Vagrant environment were properly attributed (per the-build #66).

[byrond]

Copying the .gitconfig seems to be a common example:
https://www.vagrantup.com/docs/provisioning/file.html

We could either add that into the Vagrantfile or include it with the other Ansible provisioning.

My .gitconfig has a global gitignore specified, so that path would need to be translated and that file copied in, too (if that's a frequent inclusion).

[byrond]

We also may want to prompt the user to configure Git, if they don't have a .gitconfig.

[becw]

Released in version 2.2.2. Thanks, @byrond!