By Gloria Dickie and Tanvi Mehta LONDON/NEW DELHI (Reuters) -Eight radio-collared African cheetahs step out on to the grassland of Kuno National Park in central India, their final destination after a 5,000-mile (8,000 km) journey from Namibia that has drawn criticism from some conservationists. The arrival of the big cats – the fastest land animal on Earth – coincides with the 72nd birthday of Indian Prime Minister Narendra Modi, who released the the first cat into the park on Saturday. It is the culmination of a 13-year effort to restore a species which vanished from India some 70 years ago. …