Dozens of Wynn Resorts supporters flocked to Broadway in Everett yesterday afternoon for an impromptu block party to celebrate the city being named home to the lone Boston-area casino license.“This is actually the catalyst to put the city of Everett on a worldwide map,” said Paul Dobbins, 44, a lifetime resident of the city, as he looked around Everett Square trying to imagine the changes the city will see in the coming years.