added column checks to the shp file importer
added column checks to the shp file importer

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