merging into mxnet repo

I propose to merge mxnet.cpp into mxnet project.
1. It will attract more attention to mxnet.cpp.
2. It will enable integrated test with mxnet, so that future checkins to mxnet will not break mxnet.cpp

Start by reviewing the mxnet.cpp project and the MXNet project to determine what “merge” would involve. Clarify the repository, build, and integrated-test boundaries before proposing a plan. Done means the projects have an agreed integration path and future MXNet checkins can be tested against mxnet.cpp.

Rédigé par le modèle d'indexation à partir du texte de l'issue.