In a blow to the GSEs and their supporters, the Department of Housing and Urban Development this week finalized significantly tougher affordable housing goals for Fannie Mae and Freddie Mac that will be phased in over the next four years. Significantly, HUD backed away only slightly from the controversial rule proposed last spring. The final regulations, published in the Nov. 2 Federal Register, hike the overall percentage of Fannie’s and Freddie’s business that must be…