force marker-overlap in bubble map thematics. fixed #439
force marker-overlap in bubble map thematics. fixed #439

dbirchak/cartodb,nyimbi/cartodb,bloomberg/cartodb,nuxcode/cartodb,splashblot/dronedb,bloomberg/cartodb,nuxcode/cartodb,UCL-ShippingGroup/cartodb-1,splashblot/dronedb,raquel-ucl/cartodb,nuxcode/cartodb,bloomberg/cartodb,future-analytics/cartodb,CartoDB/cartodb,nuxcode/cartodb,codeandtheory/cartodb,dbirchak/cartodb,DigitalCoder/cartodb,nyimbi/cartodb,future-analytics/cartodb,bloomberg/cartodb,raquel-ucl/cartodb,splashblot/dronedb,UCL-ShippingGroup/cartodb-1,nyimbi/cartodb,codeandtheory/cartodb,DigitalCoder/cartodb,UCL-ShippingGroup/cartodb-1,nyimbi/cartodb,CartoDB/cartodb,dbirchak/cartodb,nyimbi/cartodb,codeandtheory/cartodb,CartoDB/cartodb,raquel-ucl/cartodb,CartoDB/cartodb,raquel-ucl/cartodb,DigitalCoder/cartodb,thorncp/cartodb,DigitalCoder/cartodb,dbirchak/cartodb,codeandtheory/cartodb,thorncp/cartodb,DigitalCoder/cartodb,CartoDB/cartodb,codeandtheory/cartodb,raquel-ucl/cartodb,future-analytics/cartodb,future-analytics/cartodb,thorncp/cartodb,UCL-ShippingGroup/cartodb-1,dbirchak/cartodb,splashblot/dronedb,splashblot/dronedb,bloomberg/cartodb,thorncp/cartodb,nuxcode/cartodb,UCL-ShippingGroup/cartodb-1,future-analytics/cartodb,thorncp/cartodb