Shares of Workday popped 9% on Wednesday after activist investor Elliott Investment Management announced a $2 billion stake in the company.Workday announced a multi-year plan to enhance its operating model and capital allocation framework on Tuesday, and Elliott said it believes the plan will drive "substantial long-term value creation.""We believe CEO Carl Eschenbach, CFO Zane Rowe and the entire Workday team have made substantial progress in recent years, positioning Workday as a unique software franchise ...