One of Chicago Mayor Rahm Emanuel’s former top advisors and the ex-chief data officer for the city of Chicago have launched a VC firm to fund startups that are tackling urban problems. David Spielfogel, who joined Mayor Emanuel’s staff in 2011, and Brett Goldstein, the city’s CDO from 2011 to 2013, announced the launch of Ekistic Ventures, a VC firm that plans to invest in startups that “make cities more efficient and equitable.” Ekistic Ventures is launching with a $15 million fund that will invest…