washington u.s. special counsel robert mueller unveil trove document friday show say irrefutable evidence president donald trump former campaign manager paul manafort violate court gag order ghost-writing opinion piece design improve public image 41-page court file prosecutors provide email copy document track edit draft materials say prove manafort write positive article political work ukraine opinion article publish thursday english-language ukrainian newspaper also closely track talk point manafort business associate rick gate create far back august 2016 manafort force resign trump campaign special counsel mueller produce evidence manafort draft op-ed