Update opentripplanner-routing/src/main/java/org/opentripplanner/gtfs/GtfsLibrary.java

Support all HGV route_types. Some already supported by Google Transit and also in some official feeds (Berlin OpenVBB)
Source of the list: https://groups.google.com/forum/?fromgroups=#!msg/gtfs-changes/keT5rTPS7Y0/71uMz2l6ke0J