Charli XCX Sets US Headline Tour; High Profile Dates Celebrate Upcoming Debut Album Featuring the Hit Single, "You're The One" and the YouTube Smash, "You (Ha Ha Ha)"; UK Angel-Pop Sensation Takes Texas by Storm With Series of Spectacular SXSW Showcases; Non-Stop Live Schedule Also Includes Support Slot Alongside Marina & The Diamonds, as Well as Eagerly Anticipated Bonnaroo Set "TRUE ROMANCE" Arrives at Last on April 16th