Although Dollar General (DG)  and Dollar Tree (DLTR)  stock are still well off their 52-week highs, both have started to make a sharp rebound this year thanks to turnaround strategies that are aimed at improving operating efficiency.Ahead of their Q1 results this week, investors are certainly wondering if the rebound in Dollar General and Dollar Tree stock will continue with the discount retailers set to release their quarterly reports on Wednesday, June 3, and Thursday, June 4, respectively. Dollar General ...