Chelsea have confirmed the signing of England forward Raheem Sterling from Manchester City in a £50m deal.   Sterling, 27, has signed a five-year contract at Stamford Bridge.     City signed Sterling from Liverpool in a £49m deal in 2015. He went on to score 131 goals in 339 games, winning four Premier League titles.   Capped 77 times by England, Sterling is Chelsea boss Thomas Tuchel's first major signing since the Todd Boehly-led takeover.   "I've obviously achieved a lot in my career so far, but there is still so much more to achieve and I'm really looking