Eli Broad is a housing and insurance tycoon whose California-based Eli and Edythe Broad Foundation has poured hundreds of millions into “transforming” K-12 urban education by training administrators and supporting charter schools, merit pay and other market-based reforms. And now, Broad wants to do even more, trying to lead a campaign to raise nearly half a billion dollars to open enough charter schools to enroll nearly half of the students in the country’s second-largest school district….