added markdown library in js_files for Gruntfile
added markdown library in js_files for Gruntfile

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