use pytest<2.8 due to warning regression
use pytest<2.8 due to warning regression

doclements/python-rasterstats,perrygeo/python-raster-stats,doclements/python-rasterstats,perrygeo/python-rasterstats,ozak/python-raster-stats,perrygeo/python-raster-stats,perrygeo/python-rasterstats,ozak/python-raster-stats