Make GSL random distributions initialize with the sage random state functions

This means that Sage's randstate set_random_seed function will make the
GSL distributions also be predictable (for doctests, random matrices, etc.)
Delete #random on some matrix constructor doctests that now depend on Sage's random state
Merge branch 'develop' into t/15887/ticket/15887
Conflicts:
	src/sage/gsl/probability_distribution.pyx
Fix output precision.
Change the max seed to 2^31.
Fix doctests for new random output.
Add rel tol for numeric noise.
Merge commit '3b993ee0ebc93555634876b6f3fe3938854530c0' into t/15887/ticket/15887

Conflicts:
	src/sage/gsl/probability_distribution.pyx
Trac #15887: Make GSL random distributions seed from Sage's random state

GSL's random state currently seeds from python's random state, not from
Sage's random state.  These changes make it so that Sage's
set_random_seed() function
affects the GSL distributions.

This fixes #15090 as well.

URL: http://trac.sagemath.org/15887
Reported by: jason
Ticket author(s): Jason Grout
Reviewer(s): Andrey Novoseltsev, Volker Braun