renamed WeightCalculation into Weighting
made DistanceCalc into interface (new DistanceCalcEarth implementation)
GraphStorage into interface (new GraphHopperStorage implementation); moved some methods from Graph to GraphStorage
FlagEncoder.flags => use FlagEncoder.setProperties or separate setAccess and setSpeed method
replacing Graph.edge(a,b,dist,flags) by Graph.edge(a,b).setDistance().setFlags()