Mortgage banking income rose substantially in the second quarter of 2015 mostly because lenders sold more loans in the secondary market, but the outlook for the second half of the year is murkier. Commercial banks and thrifts sold $198.64 billion of home loans during the second quarter, according to an Inside Mortgage Trends analysis of call-report data. That was up 19.9 percent from the first three months of the year, and it represented the busiest ... [Includes one data chart]