databases/grass8: New port

After more than 3 years of development the new stable release GRASS GIS 8.0 is
available. Efforts have concentrated on making the user experience even better,
providing many new useful additional functionalities to modules and further
improving the graphical user interface.

Breaking news: new graphical user interface with entirely rewritten
startup sequence!

In total, it comes with almost 1,300 fixes and improvements with respect to
the previous stable releases 7.8.x.

See: https://trac.osgeo.org/grass/wiki/Grass8/NewFeatures80

          Geographic Resources Analysis Support System
                           (GRASS GIS)

An open source Geographical Information System (GIS) with raster,
topological vector, image processing, and graphics production functionality
that operates on various platforms through a graphical user interface and
shell in X-Windows. It is released under GNU General Public License (GPL).

WWW: https://grass.osgeo.org/