Added exception class to map arbitrary error codes to C++ exceptions

[guruofquality]

Is it possible to actually throw the exception with a template, rather than creating a templated function to throw it?

Like this:

template <typename BaseException>
class ExceptionForErrorCode : public BaseException
{
public:
    ExceptionForErrorCode(int errorCode, const std::error_category& category);
}

and thrown like that:

throw ExceptionForErrorCode<SystemException>(EINVAL, category);

i think its more syntactically like c++'s intention for exception and it doesnt add to the callstack. But I dont know if I just made up something impossible.

[ncorgan]

Rebased off of master and refactored as described