Using Fastops Library for Functions Exp, Log, Sigmoid, Tanh

Using FastOps library for functions exp, log, sigmoid, tanh. FastOps is a fast vector math library from Michael Parakhin (Yandex CTO). Improved performance of exp and log functions more than 6 times. The functions exp and log from Float32 argument will return Float32 (in previous versions they always return Float64). Now exp(nan) may return inf. The result of exp and log functions may be not the nearest machine representable number to the true answer. #6254 (alexey-milovidov) Using Danila Kutenin variant to make fastops working #6317 (alexey-milovidov)