contract Ownable {

  address public owner;

  /**
   * @dev sets owner of contract
   */
  function Ownable() public {
    owner = msg.sender;
  }

  /**
   * @dev changes owner of contract
   * @param newOwner New owner
   */
  function changeOwner(address newOwner) public ownerOnly {
    require(newOwner != address(0));
    owner = newOwner;
  }

  /**
   * @dev Throws if called by other account than owner
   */
  modifier ownerOnly() {
    require(msg.sender == owner);
    _;
  }
}
function changeOwner(address newOwner) public ownerOnly {
    require(newOwner != address(0));
    owner = newOwner;
  }
/**
 * @dev changes owner of contract
 * @param newOwner New owner
 */