This commit was manufactured by cvs2svn to create branch
'compiler_supported_error_messages'.

svn path=/branches/compiler_supported_error_messages/boost/boost/function/; revision=13249
errors.hpp:
  - Check use of Boost.Function and emit reasonable error messages

function.hpp:
function_template.hpp:
  - Updated to use compiler-supported error messages

svn path=/branches/compiler_supported_error_messages/boost/boost/function.hpp; revision=13250
bad_error_eg.cpp:
  - Example of error messages with and without compiler help

svn path=/branches/compiler_supported_error_messages/boost/libs/function/; revision=13251