[C++] Implement join
[C++] Implement join

colincross/kati,google/kati,shinh/kati,colincross/kati,shinh/kati,colincross/kati,pombredanne/kati,shinh/kati,pombredanne/kati,pombredanne/kati,shinh/kati,danw/kati,google/kati,pombredanne/kati,colincross/kati,google/kati,google/kati,dalinaum/kati,shinh/kati,danw/kati,danw/kati,danw/kati,dalinaum/kati,google/kati,dalinaum/kati,danw/kati,colincross/kati,pombredanne/kati,pombredanne/kati,colincross/kati,shinh/kati,dalinaum/kati,dalinaum/kati,danw/kati