Construction this year for Freddy’s Frozen Custard & Steakburgers stores will be at the fastest rate in the chain’s history. The 10-year-old company, based in Wichita, Kan., is slated to open 27 more new stores this year. In addition to nine company-owned stores, Freddy’s has 52 franchised units in Arizona, California, Colorado, Iowa, Kansas, Missouri,…