Nick Vivarelli International Correspondent In the early 1970s, Scottish singer-songwriter Donovan wrote and recorded songs for the English version of Italian director Franco Zeffirelli’s film “Brother Sun, Sister Moon,” about the early years of St. Francis of Assisi, that evoked the “flower power” hippie movement and developed a cult following. Half a century later, Donovan traveled to Italy last week to watch a freshly restored version of the film in two celebratory events.