BOSTON — Massachusetts drivers will soon have an opportunity to purchase a "Boston Strong" license plate.Gov. Deval Patrick on Friday signed into law a bill creating the specialty plate. Proceeds from sales of the $50 plate will help victims of the Boston Marathon bombing.The phrase "Boston Strong" became popular after the April 15, 2013 attack that killed three people and injured more than 260.Along with those words, the plate will include a design showing support for those most affected by the bombing.