add max2 method to DoubleSeq
add max2 method to DoubleSeq

joprice/factorie,zxsted/factorie,pogren-oracle/factorie,factorie/factorie,strubell/factorie,hlin117/factorie,Craigacp/factorie,malcolmgreaves/factorie,melisabok/factorie,digitalreasoning/factorie-scala-210,asubbaswamy/factorie,patverga/factorie