A naive acceptance-rejection sampling algorithm, based on bounding the
density (with respect to the distance from mu) with a constant. For large
kappa, this method grows inefficient. For kappa == 100, about 13 tries
are needed per success. For kappa == -100, about 18 tries are needed.
See also
Other random:
rbing,
rfb(),
rkent(),
rrot(),
runif.spherical(),
vonmises-fisher

