[boost] [random] Update for better TR1 compliance

I've checked in changes to the Boost.Random library that add constructors and seeding for both template<class Generator> and unsigned long arguments, thereby moving Boost.Random one step further towards TR1 compliance. The random_test.cpp program now has basic tests for this feature. In order to guide overload resolution, I've used boost::enable_if<> and type traits to make sure that integral arguments don't try to call the "template<class Generator>" overloads. This could mean decreased compiler support, sorry. It works for me with gcc 3.4.3. Jens Maurer