DOC: whatsnew entry for total_positions_value bug fix
DOC: whatsnew entry for total_positions_value bug fix

enigmampc/catalyst,quantopian/zipline,magne-max/zipline-ja,enigmampc/catalyst,florentchandelier/zipline,florentchandelier/zipline,alphaBenj/zipline,nborggren/zipline,bartosh/zipline,quantopian/zipline,humdings/zipline,bartosh/zipline,umuzungu/zipline,alphaBenj/zipline,humdings/zipline,magne-max/zipline-ja,wilsonkichoi/zipline,grundgruen/zipline,Scapogo/zipline,umuzungu/zipline,wilsonkichoi/zipline,nborggren/zipline,grundgruen/zipline,Scapogo/zipline