Fixes #1764 

* Add a doc page to explain random number generator handling

* replace deprecated numpy.random.random_integers with randint

* First set of random_state decorator updates... utils and some generators

* protect numpy import from failure is not there

* fix doctests in randomness.rst

* Update algorithms for new random_state paradigm

* Fix tests dependent on python version

* Update random_state paradigm in rest of the modules

* fix tests for wierd cases.

windows 32bit doesn't like big seeds.
smallworld wasn't sending seed to utils.discrete_sequence

* Add tests.  Rewrite randomstate interface class to fix tests

* anogther tweak for osx with no deps

* improve doc examples for seed. Check all functions for seed independence.

Calling with int seed should not affect global RNG

* Add testing script and add more variates to RandomInterface

* fix typo and remove unneeded file causing nodetest trouble

* fix doctest for randomness.rst