Fast computation of descriptive statistics in ruby using native code and SIMD

This gem provides fast computation of descriptive statistics (min, max, mean, median, 1st and 3rd quartiles, population standard deviation) for a multivariate dataset (represented as a 2D array) in ruby.It is ~11x faster than an optimal algorithm in hand-written ruby, and ~4.7x faster than the next fastest available ruby gem or native extension (see benchmarks below).