[Random] Brokem MSVC workaround

[Richard Webb <richard.webb@…>]

The problem in unform_int described in ticket #1423 also exists in the uniform_smallint class, and can be fixed in the same manner (disabling the workaround for VC9). This isn't found by the regression tests as the uniform_smallint tests are commented out in random_test.cpp.

However:
1) The workaround in question referes to an '_impl' class member, which no longer exists.
2) The workaround is inside a "!defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)" block. BOOST_NO_MEMBER_TEMPLATE_FRIENDS is defined for all MSVC versions prior to 9, so it's never used anyway.

Basically, the workaround seems to serve no purpose.

[Steven Watanabe]

(In [51413]) Enable stream operators on msvc. Fixes #1068. Fixes #1691