git-fame is inadequate for summarizing contributors

[jaraco]

In casperdcl/git-fame#96, I reported an issue about git-fame not having a good way to render the email and author together. I thought I had a hack in place to make it viable until there was proper support, but a fellow commenter there pointed out that the technique doesn't actually work because there isn't a 1:1 mapping of name to email in git commits. We observed this issue in coherent-oss/coherent.cli#11.

We need to figure out another solution, even if that means forking git-fame or writing a custom summarizer.