WWA has new contact email

The main contact email for the Western Water Assessment is now wwa@colorado.edu, changed from the previous wwa@noaa.gov. While we have close ties with NOAA, being a RISA program funded by the NOAA Climate Program Office and physically located in the NOAA ESRL building, we're formally a program of the University of Colorado Boulder. Our new email better reflects our affiliation with the university.