Slade Jones, the teenaged son of Derby and Gold Cup winner Jonathon Jones and the grandson of the legendary Challenor Jones, is joining the jockey colony at Woodbine Racetrack in Toronto, Canada, this week. The 16-year-old, who was born in Canada, is leaving with his father on Thursday and could have his first ride at the weekend. “I am very excited. I always wanted to be a jockey and to …