Use new temp file directory.
Use new temp file directory.

We created a new scratch directory that matches EC2 mounted temp space and
supplied this as a setting in commit 21916b. This switches temporary images to
be downloaded there rather than at /tmp.

azavea/raster-foundry,kdeloach/raster-foundry,azavea/raster-foundry,raster-foundry/raster-foundry,raster-foundry/raster-foundry,aaronxsu/raster-foundry,raster-foundry/raster-foundry,kdeloach/raster-foundry,azavea/raster-foundry,kdeloach/raster-foundry,kdeloach/raster-foundry,aaronxsu/raster-foundry,aaronxsu/raster-foundry,aaronxsu/raster-foundry,azavea/raster-foundry,kdeloach/raster-foundry,azavea/raster-foundry