The Giants have a chance to do something with John Harbaugh that they haven’t been able to do in years: Win on the margins. Special teams. Situational football. Disciplined play until the other team cracks. These are the advantages Harbaugh’s leadership and experience hopefully can create for a flailing Giants team that is trying to figure out how to finish and put a full game together. The Giants’ Week 11 game against the Jacksonville Jaguars a…