This merges duplicate duplicate authors in local git commands, mainly
`git log` and `git shortlog -sne`. I have been mostly guessing who is
who and what is their primary identity so this needs heavy review, but
maybe this can at least be a base for someone to write a .mailmap in the
future.
This may also make scraping emails easier for spamming than git does by
default.
Aminda Suomalainen