Given that Captain America: Civil War had long been confirmed by the time Age Of Ultron was released, set to pit Iron Man against Captain America, it was a surprise when at the end of the film Tony Stark and Steve Rogers were on good terms with each other. However, there was one scene that make may be taken as a potential setup for the film, between Rogers and Maria Hill. It hasn't been revealed which side she's on in Civil War, but on the basis of this it seems as though it will be Stark's (which is the same in the comics). It shows her and Cap discussing Ultron and the chaos he's causing, prompting the following exchange:
Hill: "What if he's just doing what he's supposed to?" Rogers: "If I thought Ultron were bringing peace, I'd hang up my shield." Hill: "Would you?"
She asks that last part rather pointedly, and it's an early indication of their differing mindsets, and the potential for some rifts to develop between the two teams, which will be explored much more next year.