Performing arts aplenty
by Janos Gereben Dance, opera, symphonic, choral and jazz music are blooming in a season that also offers outdoor, moderately-priced (and some free!) performances as well as multi-event festivals. Here's a brief sampling: Yerba Buena Gardens Festival: The 15th anniversary season presents 100 free events, including the Dafnis Prieto Sextet (June 13), Azucar con Aché (June 18), S.F. Lesbian/Gay Freed…