Add new engine based on Richard Brent's xorgens-4096 PRNG

[Pencroff]

Hi.
Could you please add additional engine random generation based on Richard Brent's xorgens-4096 PRNG algorithm (source)
I did some tests and it looks faster then Math.random and has the widest range.
Look at simulation examples:

• Math.random
• Internal mt19937
• xor4096

Thanks,
Sergey

[rawr51919]

This seems like a relatively useful engine for this. I'm on board with the idea, too. What do you think, @ckknight?

[rawr51919]

@ckknight could this still be implemented for v3.0.0?