Emma Watson, Jessica Chastain and Cheryl Cole were a few of the stars to add Hollywood style and glamour to the 66th annual Cannes Film Festival.Watson shimmered in an elegant monochrome Chanel floor-length dress as she attended The Bling Ring's screening, while Chastain stunned in a simple white Versace gown with a pendant belonging to the late Elizabeth Taylor.And Cole dazzled in a sheer sequine