message: Change leave room button text, OK -> Leave
diff: @@ -1034,6 +1034,7 @@ export default React.createClass({
  { warnings }
  </span>
  ),
  + button: _t("Leave"),
  onFinished: (shouldLeave) => {
  if (shouldLeave) {
  const d = MatrixClientPeg.get().leave(roomId);
  