random (mersenne_twister<>::seed()): Fix per tr1/5.1.4.2, p8.

2006-06-05  Paolo Carlini  <pcarlini@suse.de>

	* include/tr1/random (mersenne_twister<>::seed()): Fix per
	tr1/5.1.4.2, p8.
	* include/tr1/random.tcc (mod_w): Add.
	(mersenne_twister<>::seed(unsigned long)): Fix per tr1/5.1.4.2, p9.
	(mersenne_twister<>::seed(Gen&, false_type)): Adjust to use mod_w.
	* testsuite/tr1/5_numerical_facilies/random/mt19937.cc: Fix
	expected result per tr1/5.1.5, p2.
	* testsuite/tr1/5_numerical_facilies/random/mersenne_twister/
	cons/default.cc: Adjust.

	* include/tr1/random (exponential_distribution<>::operator()()): Fix.

From-SVN: r114412