gdal needs for rasterizing global maps

[kejohnso]

We use this script to rasterize the global maps, which depends on GDAL. The oq-engine GDAL wheel seems to be missing some of the GDAL functionalities that we use (i.e. gdal_rasterize), and so a separate installation via brew (or elsewhere) is required, which can cause problems with the GDAL installed in our openquake environment.

[pslh]

This script is used only by the GEM Hazard team, and is not intended for use by others.
We should consider replacing this script with a Python code that uses the GDAL functions directly rather than the executables; it would also make sense to investigate the possibility of using multiple CPU cores to e.g. process one layer per core (RAM permitting). It may also make sense to install this on a server/workstation so as not to tie up resources on a laptop.