Under growing pressure from investors, lenders are divulging more information about the alternative mortgage products in their portfolios and securitizations. And so far, the sneak peeks aren’t all that positive. In their recent public filings, the alternative mortgage market’s largest players were nearly unanimous in reporting a substantial increase in negative amortization on the loans in their portfolios – a sign that many borrowers with option adjustable-rate mortgages are keeping their payments as low as…