HEARTWARMING: Lily, a 24-year-old waitress, had no idea that she was serving Manchester United superstar Lisandro Martinez. Polite and discreet, Martinez enjoyed his meal without attracting attention. But as he left, he placed a folded receipt on the table… and walked out with a smile. Curious, Lily opened it, but within minutes was in tears. What Martinez wrote was more than just a thank you note