Basic Makefile for building unittest program and docs
Sort std.random2.distribution entries in alphabetical order
Use UniformRNG as default template variable name for RNGs
Use rng as standard name for UniformRNG variables
Discrete distribution that offers a range-based equivalent of dice

This is adapted from Chris Cain's RandomDie submission to Phobos
in https://github.com/D-Programming-Language/phobos/pull/1702

The alternative name is chosen by analogy to Boost.Random and the
C++11 standard.
Correct author information for std.random2.distribution
Doc paragraph explaning function vs. range choice for distributions
Discrete distribution function attributes and unittests
std.random2.device module for non-deterministic random sources
Basic Posix random devices based on /dev/random and /dev/urandom
Comprehensive benchmarks of all RNGs, distributions and adaptors

Random devices are not included in the benchmark because they are
in any case significantly slower.
Comprehensive benchmarks of old std.random