Draws a filled or stroked rounded rectangle

@param {String} args The arguments to the command
function RrectCommand(args) {
    var parsed = new statements.ArgumentStatement(args);

    if (parsed.args.length < 5) throw new SyntaxError('RRECT command requires 5 arguments');
    this.x1 = parsed.args[0];
    this.y1 = parsed.args[1];
    this.x2 = parsed.args[2];
    this.y2 = parsed.args[3];
    this.radius = parsed.args[4];
    this.stroke = parsed.args.length > 5 ? parsed.args[5] : false;
}