Provides density, distribution function, quantile function and random
generation for the split normal and split-t distributions, and computes their
mean, variance, skewness and kurtosis for the two distributions (Li, F,
Villani, M. and Kohn, R. (2010)
Changes in version 0.2.0 (2018-03-15)
o Include split normal distribution and related moment functions based on Villani and Larsson (2006).
Changes in version 0.1.1 (2017-03-02)
o Include split-t distribution and related moment functions based on Li, Villani and Kohn (2010).