* Make the library modular usable.
* Switch to library requirements instead of source. As source puts extra source in install targets.
* Clean up build dependencies.
* Remove external build references and avoid custom project loading.
* Use relative paths to declare config sub-projects.
* Add missing NO_LIB usage requirements.
* Add missing library ref.
* Add missing import-search for cconfig/predef checks.
* Add requires-b2 check to top-level build file.
* Update dependencies.
* Bump B2 require to 5.2
* Update copyright dates.
* Move inter-lib dependencies to a project variable and into the build targets.
* Remove custom symbolic project names for config subprojects. And use project root relative targets.
* Move private deps to the build project.
* Put back default boost locale link as locale build is now fixed.
* Set default address-model and architecture to avoid extra/custom detection logic. Put back missing check and config rules.
* Adjust doc build to avoid boost-root references.
* Fix ref to predef.jam location.
* Have B2 build use same deps as CML for per-target private/public.
* Add log dep to log_setup, as it's needed on some platforms.
* Add boost_log_with_support target to mirror CML.
* Fix platform specific winapi dependency spec.
