The new giant of cruising, Royal Caribbean's Symphony of the Seas, finally has reached its year-round home.  Unveiled earlier this year in Europe, the much-awaited, 228,081-ton vessel pulled into the Port of Miami on Friday before dawn after a 12-night voyage from Barcelona. The arrival came a day after the 18-deck-high vessel made a brief stop at Port Canaveral, Florida — its first call in North America.  Arriving in the vicinity of Miami's cruise port before 3 a.m. on Friday, Symphon