Suggest emails and names based on `user.email` & `user.name` Git settings

[rimutaka]

If a repo has multiple commiters with different emails, but the same or a very similar looking name the app should suggest adding them to the list of --emails

user.name should be used to suggest the pubic name and contact.

Caveats:

1. Adding them automatically is error-prone. The user may not want those commits. It could be someone else. Ask first.
2. Reminding every time will be annoying. There should be a list of suggested IDs to back off at some point.

Via @marcoslopes. Thanks for the idea!