Log Message:
Update to 1.4.30

Upstream changes:
16 June 2017: statmod 1.4.30

- Bug fix to qinvgauss(). In some case the gamma approximation used
  for small right tail probabilities was taking the initial value
  outside the domain of convergence.

27 February 2017: statmod 1.4.29

- rinvgauss() now accurately handles large or infinite values for the
  mean or dispersion.

26 February 2017: statmod 1.4.28

- R_registerRoutines is now used to register the Fortran subroutine
  gaussq2.

- pinvgauss() and qinvgauss() now use a gamma approximation when the
  coefficient of variation is very small.

17 December 2016: statmod 1.4.27

- qinvgauss() now supports mean=Inf.