Added MANIFEST.in

[ocefpaf]

In this PR:

• a lean MANIFEST.in that creates a source dist with the colormaps, code, and bare metadata (README.rst and LICENSE.txt)
• avoid the eval on the test

Note that the test is a simple: 'does this work' rather than a figure comparison test. I am not sure if figure comparison is necessary here though. But we can improve this a little bit. They can fail silently. We can add things like a list of the expected colormaps.

Also, the colormaps are no longer in the main namespace as the previous test expected . (They where failing silently.) Do you want them there? Or the API cmocean.cm.<cmap> is OK?

[kthyng]

Ok great. Which way do you think would be best for where the colormaps are located?

[ocefpaf]

I like cmocean.cm.<cmap>, but I don't have any strong options about it.

[kthyng]

Ok so it is good as is then, I think.