From Variety' :- Snow White' actress set for Voltage action pic. "Snow White and the Huntsman" star Kristen Stewart is set to topline "Cali," a gritty action pic set in Los Angeles that will be produced by Voltage Productions and New School Media. Michael Diliberti ("30 Minutes or Less") wrote the script, which follows Mya (Stewart) and Chris, a pair of San Fernando Valley lovebirds with a pe…