Added some further type traits classes. Moved the implementation classes into the impl namespace. Added the user classes.
 On branch master
 Changes to be committed:
	modified:   bin/Debug/libmp
	modified:   mp/is_associative_container.hpp
	new file:   mp/is_bitset.hpp
	new file:   mp/is_container.hpp
	modified:   mp/is_container_adaptor.hpp
	modified:   mp/is_sequence_container.hpp
	new file:   mp/is_string.hpp
	new file:   mp/is_tuple.hpp
	modified:   mp/is_unordered_associative_container.hpp
	modified:   test.cpp