0.0 quantile and 1.0 quantile

[Allineer]

The library crashes when querying 0.0 or 1.0 quantile.
I agree, this makes little sense, but leaders can do it:

pandas:

Value between 0 <= q <= 1, the quantile(s) to compute.

numpy:

Quantile or sequence of quantiles to compute, which must be between 0 and 1 inclusive.

R:

The smallest observation corresponds to a probability of 0 and the largest to a probability of 1.

[antonmyronyuk]

Hi, see #1 (comment)

Original lib works fine with both 0.0 and 1.0