boost.build script to build libbson project
-- on this stage it is depending on CMake and generated project (With CMake)
bson-config is imitated using boost library.
bson-version is copied from VS project generated by CMAKE

Perhaps it is a mess
A short info for this fork
starting MinGW/GCC/WIndows support
Try to use gnu99 c dialect instead of c99 (just an experiment)
bugfix: size_t redefinition
in case libbson is used from C++ project size_t appeared to be already-defined
so in case of C++ we don't need this
complete MINGW/Windows compatibility Win32/x64
-- Fixes are not ultimate and rude a little
-- pay attention on instruction-set.
   If it is specified incorrectly __sync_add_and_fetch_8 undefined reference may appear

-- fixes in Jamfile
-- add examples how to invoke
== Fix undefined reference GetTickCount64 (bson-clock.c)
== Fix for __sync_fetch_and_add_8/InterlockedIncrement64 undefined reference
== Fix for strerror_s/strerror_r undefined reference
== Fix for undefined __TRUNCATE
== Force use pthread for GCC/Windows
Everything here is done for Mingw
Merge branch 'mingw-adjuast'