MILAN (Reuters) - An Italian judge said on Monday there was evidence showing oil groups Eni and Royal Dutch Shell were aware that their 2011 purchase of a Nigerian oilfield would result in corrupt payments to Nigerian politicians and officials.Italy's Eni and Shell bought the OPL 245 offshore field for about $1.3 billion (1.03 billion pounds). The Milan judge made the comment in handing down her reasons for the September conviction of Nigerian Emeka Obi and Italian Gianluca Di Nardo, both..