Extracted map layers management in map_layers_add, so the user can easy customise his/her layers
Extracted map layers management in map_layers_add, so the user can easy customise his/her layers

CodeForJerseyCity/interactive-transit-map,vasile/transit-map,CodeForJerseyCity/interactive-transit-map,eubr-bigsea/transit-map,vasile/transit-map,vasile/transit-map,eubr-bigsea/transit-map