Contribution to cover C++11 functionality

[Ilya Yaroshenko via Digitalmars-d]

Hi,

Mir Random has [1, D] 16 out of 20 [2, C++] random number 
distributions.

Remaining 4 are:

1. piecewise_constant_distribution
2. piecewise_linear_distribution
3. binomial_distribution
4. negative_binomial_distribution

[1] http://docs.random.dlang.io/latest/mir_random_variable.html
[2] 
http://en.cppreference.com/w/cpp/concept/RandomNumberDistribution

Any takers?

Thanks,
Ilya