fill voids
trying to make the README text better
we need python-gdal for gdal_fillnodata.py
add cleanup instructions
preformatted text should be on a single line
readme change to $PATH instead of PATH
add QGIS color ramps
use comp-op rather than mode in mapnik stylesheet due to a change in the mapnik api
fix 04-merge to work globally
use LZW compression to save a lot of disk usage
also fix contour loader to work globally
add some error checking to the bounds
use a void filled DEM for the contour creation step
add a counter to make sure that some SRTM3 tiles were turned into contours
drop intermediate table and vacuum analyze as soon as possible to save space
Fixed merging western latitudes