Siddhartha Vaidyanathan on two spinners who are on their way to inspire so many more Two legspinners. Both with a whiff of mystery. Both capable of attacking as well as defending. Both from countries without Test status. Both waiting their turn in the opening week of this year’s GT20. And both making the most of their first two chances. Sandeep Lamichhane, the prodigy from Nepal, recently turned 19. Hayden Walsh Jr., born in the US Virgin Islands, raised in Antigua and now playing for the USA national team, is 27.…