Kismet to KML converter.

Tried a few converters, wasn't impressed. Hopefully this will eventually
use polygons to display a pseudo 3d view of network coverage and whatever
other swanky advanced features Google Earth supports

HOWTO:
 Run the script with the prefix of your gps and xml files:

 mykismetrun.[net]xml
 mykismetrun.gps[xml]

 perl kismet2kml.pl mykismetrun

TODO:
-Use power levels to weight network centre
-Sort gps points by time and stamp them with their timestamp
-Color networks distinctly from their neighbours
-Add in KML tour to navigate the whole path
-Use KML styling to distinguish networks on highlight
-Probably a lot of other stuff I can't think of