Use STL implementation over in-house version

[prince-chrismc]

Follow up from #71

There are several c++17 and fundamentals v2 which have been copied to provide compatible c++11 support.

Type	feature macro	header
make_void	__cpp_lib_void_t (maybe)	<type_traits>
void_t	__cpp_lib_void_t	<type_traits>
nonesuch	__cpp_lib_experimental_detect	<experimental/type_traits>
is_detected	__cpp_lib_experimental_detect	<experimental/type_traits>

Despite this being common practice, we should be checking the feature macro and when available use the STL implementation otherwise fallback to the in house one for compatibility.

The travis matrix should be expanded to test on multiple cppstd versions.

\cc @Thalhammer

[Thalhammer]

I have implemented using void_t if available, however as none of my compilers support std::is_detected (yet) I'll post pone this.