Summary: Moved libs/detail/utf8_codecvt_facet.cpp to boost/detail/utf8_codecvt_facet.ipp
Author: Dave Abrahams <dave@boostpro.com>
Combine scoped enum emulation from thread library into detail/scoped_enum_emulation.hpp
ScopedEnum: Rollback last change as there are regressions on Spirit
ScopedEnum: Fix issue with native function class
Add warning to deprecated header `boost/functional/detail/container_fwd.hpp`.

Should have done this years ago, removing this header should make
modularization a tad bit cleaner.
Initialize 1.51
Chrono: Try to fix issue with WinError.h file
Thread: Try to fix 5431
Thread: Rollback last modification as it breaks regression test VeecoFTC/msvc-9.0~wm5~stlport5.2
Thread: Try again to fix 5431
Bump version number to 1.52
Detail: Merge some whitespace fixes from release.
Fix: intrin.h is available in msvc-9.0 (_MSC_VER 1500)
Fix the _WIN32_WCE >= 0x600 case.
Fix up for Arm.
Fixes #7516.
Fix stray whitespace in previous commit.
Refs #7516.
Bump version # to 1.53.0
Remove usage of deprecated macros
Fixed incorrect 'const' param for utf8_codecvt_facet::do_length
Made codecvt::do_length param constant based on the library used, not the compiler