By SAM MEDNICK, Associated Press JUBA, South Sudan (AP) — Angelo Adud needed some persuading to leave his job as a shopkeeper and become a mobile money agent in South Sudan. Yet one week into his new role, the 29-year-old already saw a return on his investment. "This is a new country and digital things are hard to understand. I was worried, what if no one comes?" he said while helping a customer withdraw