rename mapdb GTFS loader class, use Logger
draft classes for loading OSM into MapDB
Add node tracker class and test
Split out node and way loading to allow geographic and used-node filtering.

also update NodeTracker method names to match Set
Encapsulate MapDb in OSM class. Static OSM loader methods.
add sketch of "qualified modes" expressing park and ride / bike rental
more encapsulation in new GTFS code