Have config/select_stdlib_config.hpp and config/stdlib/stlport.hpp use <cstddef> instead of <utility> to determine which standard library is in use. For std lib implementations that rely on Boost components like TypeTraits, Bind, Function, or SmartPtr, this helps to avoid circular header dependency issues, since <cstddef> is much less likely to pull in Boost libraries than <utility>.
In get_pointer.hpp, switched to using <boost/config/no_tr1/memory.hpp> instead of using <memory> directly. As above, this helps avoid circular header dependency issues in Boost-supplemented std libs (specifically it avoids issues when <memory> pulls in pieces of Boost.SmartPtr).
These two changes were made in response to testing done with STLport 5.2.1 using the _STLP_USE_BOOST_SUPPORT option.
