Gary Kremen, a Silicon Valley tech entrepreneur who co-founded Match.com and dropped out of the race for Santa Clara County assessor earlier this week after a controversy involving semi-nude photos of him and his girlfriend being sent to a campaign aide, will step down temporarily as chairman of the Santa Clara Valley Water District. In a statement, Kremen, 58, said late Wednesday night that he will remain on the board of the water district, a government agency based in San Jose that provides drinking water and flood protection to 2 million people in Santa Clara County. But he said effective March 22, he will give up the chairman’s gavel for 60 days …