Luxury brands have been falling and department stores have been warning, so all eyes will be on Michael Kors (KORS) when it reports second-quarter earnings on Tuesday. Analysts are expecting earnings of 40 cents per share and sales of $519.3 million in the company's first Q2 since going public last December. The company has reported double- or triple-digit EPS and earnings gains since its debut. Kors has been one of the biggest IPO successes of