o  an actual dip *test*, i.e. compute a P-value for the dip statistic;
   using (spline) interpolation in qDiptab.

o  Consider an analogue qnormDiptab  which is constructed using
   rnorm(.) instead of runif(.) simulations


would be nice:

o  Visualize the l.c.m. and g.c.m. and the modal interval !
   g.c.m = greatest convex minorant =: G(x)
   l.c.m = least   concave majorant =: H(x)
