Added fix for divide-by-zero bug, which shows up as "Negative weight (osm-307690545(4269609) -> osm-307690545(-2143214080))" during building of shortest path trees.
Added fix for divide-by-zero bug, which shows up as "Negative weight (osm-307690545(4269609) -> osm-307690545(-2143214080))" during building of shortest path trees.

bmander/graphserver,bmander/graphserver