By THÉRÈSE MARGOLIS     After the Friday, Feb. 16, magnitude 7.2 earthquake and a magnitude 5.8 aftershock just one hour later – both coming close on the heels of two devastating quakes on Sept. 7 and 19 that cost Mexico nearly $30 billions in damages, destroyed more than 1,800 historical landmarks and left more than 450 people dead nationwide, Mexicans, especially