add notes about curl.js on CDN
add notes about curl.js on CDN

cujojs/curl,dfd07d/curl,runt18/curl,marian-r/curl,vtex/curl,dfd07d/curl,djkost85/curl-1,marian-r/curl,dfd07d/curl,jaredcacurak/curl,runt18/curl,cujojs/curl,jaredcacurak/curl,djkost85/curl-1,vtex/curl,vtex/curl,jaredcacurak/curl,marian-r/curl,djkost85/curl-1,runt18/curl,cujojs/curl