It was high school graduation day in many towns across Western Massachusetts over the weekend.  At Holyoke High School, 253 seniors received their diplomas, and more than 80 percent of them will be heading off to college.  The numbers were even higher in Belchertown, where 87 percent of seniors who graduated yesterday are going to college in the Fall.  Commencement ceremonies were also held in Northampton, South Hadley, and Greenfield.