Replace three links that seem broken (keep timing out)

Fix broken sgi/stl links.
Fix broken gmane link.

include/boost/mpl/if.hpp

@@ -46,7 +46,7 @@ struct if_c<false,T1,T2>
 };
 
 // agurt, 05/sep/04: nondescriptive parameter names for the sake of DigitalMars
-// (and possibly MWCW < 8.0); see http://article.gmane.org/gmane.comp.lib.boost.devel/108959
+// (and possibly MWCW < 8.0); see https://lists.boost.org/Archives/boost/2004/09/71383.php
 template<
       typename BOOST_MPL_AUX_NA_PARAM(T1)
     , typename BOOST_MPL_AUX_NA_PARAM(T2)