FLa-Z-Boy furniture stores are to expand following a recent acquisition in the southeast. (Photo by Smith Collection/Gado/Getty Images)Getty ImagesWhat a difference a few days make, even for that most horizontal of retailers, La-Z-Boy Inc.The Michigan-based company that has come to define the recliner chair sector was feeling anything but relaxed when its shares plummeted earlier this week after setting guidance below expectations.Come post-trading on Friday those shares were heading upright once again afte ...