geotrellis.util.srs
WGS 84 Web Mercator, Spherical Mercator, EPSG:900913, EPSG:3857
http://spatialreference.org/ref/sr-org/7483/
WGS 84 Web Mercator, Spherical Mercator, EPSG:900913, EPSG:3857
http://spatialreference.org/ref/sr-org/7483/