When a passionate Gypsy meets an already spoken-for Spanish Army corporal, look out. Georges Bizet’s tragic opera, “Carmen , ’’ starts the new season of “Europe’s Grand Operas,’’ screenings of live performances from Italy’s La Scala and other major European opera houses. This 2009 La Scala production stars mezzo-soprano Anita Rachvelishvili in the title role. Next up is “Aida’’ on ...