ForeclosuresMass.com said today that May foreclosure filings against Massachusetts homeowners have more than doubled, a trend that is accelerating as the housing market slows and mortgage rates increase. ForeclosuresMass.com, which tracks monthly filings by financial institutions against homeowners in the state's Land Court, said there were 1,613 filings last month, compared with 788 in May 2005. "That's over 50 a day every day of the month," said Derek Beckwith, spokesman. The biggest increases occurred in Barnstable County on Cape Cod, 96 in May 2006, up from 32 in May 2005; Suffolk County, 171, up from 71; and Bristol County, 143,...