Make use of GPU-accelerated GDAL

[jjmata]

It seems clear that one of our bottlenecks is going to be the re-projection of TIFFs when importing them to Postgres via raster2pgsql which made me wonder about parallelism or GPU acceleration. As it turns out, there is OpenCL support in gdalwarp, read here:

• http://mojodna.net/2015/01/27/resolved-gdal-on-aws-gpus.html

So, yes ... we should consider dedicated machines for raster imports that are GPU-backed.