Maintenance

[dopplershift]

A few todo list maintenance items I've been meaning to do before the next release:

• Update Travis to use python 3.7-dev for "bleeding edge" builds
• Update AUTHORS.txt for any new code contributors
• Update year in LICENSE
• Update .mailmap as needed to keep contributors unique
• Remove any spurious warnings from tests/doc/example builds. I thought when building docs locally I was seeing our own deprecation warnings, which is silly.
• Update CODEOWNERS to replace jrleeman with zbruick

This is a great way to find authors: git log --format='%aN %aE' | sort -u

I'm putting this here so I don't forget, but it's fair game if someone is exceedingly motivated. Just make sure you drop a note below if you happen to pick it up so we don't collide.

[zbruick]

Only item that remains is removal of spurious warnings.

[dopplershift]

I don't see any spurious warnings left. There's one about gridding, which happens because we have gridding in the api docs. Then there are two I see from "viridis", which occur because we have an image of all our colortables in the docs. I think this is done.