- Fix legit threading issue which shows itself on clang / macos mostly
 - Fix all warnings that I can / ignore those caused by boost
Merge branch 'master' into ChaiScript_5_0_CPP_11

Conflicts:
	include/chaiscript/chaiscript_threading.hpp
	include/chaiscript/dispatchkit/boxed_value.hpp
	include/chaiscript/dispatchkit/proxy_functions_detail.hpp
	samples/example.cpp
	src/test_module.cpp
	unittests/multithreaded_test.cpp