SOUTH African rugby captain Siya Kolisi has put pen to paper, sealing the deal on his switch to the Cell C Sharks after 11 years with Cape Town’s DHL Stormers. “I bought into the vision of the Sharks immediately – the energy around the club, the management set-up, the squad and the potential for success was so strong," said Kolisi. https://twitter.com/TheSharksZA/status/1361949234103259137 The former Stormers captain is eager to build on his career in his career “I have always had a desire to be the best, and play with the best, to reach my potential on-and-off the field, and this move…