v1.0 ihaque 5/30/06 initial version v1.1 ihaque 5/31/06 added equipartition binning

v1.2    ihaque  ???     added k-means binning
v1.3    ihaque  ???     added rendering to disk
v 1.31  ihaque  3/1/07  moved functions from EXPORT to EXPORT_OK
                        added named-argument wrappers to generate_kml_file and generate_kmz_file
                        added perldoc
v 1.32  ihaque  3/2/07  fixed documentation bug with SYNOPSIS
                        changed default font path to that for FreeSans
v 1.33  ihaque  6/22/07 added rudimentary support for altitude-mapping data
                        changed default font path to that for FreeSans

v 1.34 ihaque 9/19/07 fixed bug relating to spaces in the polygon string passed to kml_polygon