The Angry Birds movie is officially getting a sequel. While not revealing any details, Rovio Chief Executive Kati Levoranta said the company has "started planning" the second Angry Birds movie. Based on the hit mobile game series, the Angry Birds movie debuted atop the box office when it was released earlier this year. As The Wall Street Journal reports, it ended up being quite profitable, grossing $347 million USD worldwide on a budget of $73 million. Continue reading…