Update link for downloading GOES data

[CMASCenter]

The data/sat/README file and the Raster Tools documentation do not have the correct link for the GOES data:

The GOES data tool processes the Geostationary Operational Environmental Satellite (GOES) data downloaded from the Earth System Science Center (ESSC) at the University of Alabama in Huntsville. The GOES data web site is http://satdas.nsstc.nasa.gov/.

Find the correct link and update the documentation.