Duplicate copy constructors for binary::decode and binary::encode

[Niadb]

MSVC trips up here giving a warning that there are duplicate copy constructors for both decode and encode.

decoder(const decoder&);
decoder(decoder&);

inline
decoder::decoder(const decoder& d)
: _was_error(d._was_error) {
_current.begin = d._current.begin;
_current.end = d._current.end;
}

inline
decoder::decoder(decoder& d)
: _was_error(d._was_error) {
_current.begin = d._current.begin;
_current.end = d._current.end;
}
They are identical so we can remove the non-const versions-- and the problem goes away

EDIT: I see why you were doing this-- the compiler is invoking the wrong copy constructor in encode(encode), and calling the Sequence instead..

Guess the only solution is to disable this warning.