BERLIN (Reuters) - Germany's BVB building association said on Tuesday it expected overall sales to grow by 5% to 354 billion euros (304.9 billion pounds) this year and by 4.2% to 370 billion euros next year.With exports hit by trade tensions and a global economic slowdown, the bulk of Germany's economy increasingly depends on its robust domestic spending driven by record-high employment and strong demand in the construction sector.The housing sector continues to benefit from high demand for real..