Docs: Add NASA-GMAO to consortium figure

[marshallward]

This patch updates the PNG file of the consortiums in the docs to
include the NASA-GMAO group.

[codecov]

Codecov Report

Merging #31 (d3e4db2) into dev/gfdl (7ae28b8) will not change coverage.
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  Lines         71237    71237           
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  Hits          20665    20665           
  Misses        50572    50572           

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[Hallberg-NOAA]

I like the changes, but why doesn't NASA/GMAO get any users or their favorite color? In some more elaborate later version, we could perhaps consider replacing the plain circles with the logo-badges of each of their Institutions? If there is one thing that we can all learn from NASA, it is how to do branding right!