Added cartoassets stylesheet to editor-3
Added cartoassets stylesheet to editor-3

bloomberg/cartodb,splashblot/dronedb,bloomberg/cartodb,codeandtheory/cartodb,bloomberg/cartodb,splashblot/dronedb,CartoDB/cartodb,CartoDB/cartodb,bloomberg/cartodb,splashblot/dronedb,codeandtheory/cartodb,codeandtheory/cartodb,splashblot/dronedb,CartoDB/cartodb,bloomberg/cartodb,codeandtheory/cartodb,splashblot/dronedb,CartoDB/cartodb,CartoDB/cartodb,codeandtheory/cartodb