(Credit: Dutch National Opera & Ballet) The Detroit Symphony Orchestra has named young Italian conductor Jader Bignamini as its 13th music director. As music director, Bignamini will have much free reign — overseeing auditions, crafting programming and shaping a big-picture vision. Bignamini will be formally introduced as the DSO’s new maestro at 5:30 p.m. today in Beacon Park, where he’ll {…}