* Use validation classes rather than traits for Statistical functions, and some verification of nullable arguments
* Eliminate more of the issues resolved in phpstan baseline
* Extract Binomial Distribution functions from Statistical
Replace the old MS algorithm for CRITBINOM() (which has now been replaced with te BINOM.INV() function) with a brute force approach - I'll look to refine it later. The MS algorithm is no longer documented, and the implementation produced erroneous results anyway
* Exract the NEGBINOMDIST() function as well; still need to add a cumulative flag to support the additional argument for the newer NEGBINOM.DIST() function
* Rationalise validation of probability arguments
Mark Baker