CANADA STOCKS-TSX advances after Tim Hortons climbs on deal news

* TSX up 20.47 points, or 0.13 percent, at 15,619.21 * Seven of 10 main index sectors advance * Scotiabank slips, BMO gains after lenders report results * Tim Hortons surges about 8 percent By John Tilak TORONTO, Aug 26 (Reuters) - Canada's main stock index rose on Tuesday as shares of Tim Hortons Inc climbed after the coffee chain said it planned to merge with Burger King Worldwide Inc in a C$12.64 billion ($11.53 billion) deal. The companies said the cash-and-stock agr