updating nn to 6f20a8378207812218115c21837ab5360de2b472 , cunn to 72c7a8ae44d1718989ebf5716f06263a1b33870a and nngraph to c131490dc13ad52db212a8ffd64407e9eaee8e33
updating nn to 6f20a8378207812218115c21837ab5360de2b472 , cunn to 72c7a8ae44d1718989ebf5716f06263a1b33870a and nngraph to c131490dc13ad52db212a8ffd64407e9eaee8e33

Summary: updating packages from upstream

Reviewed By: jgehring

Differential Revision: D3312226

fbshipit-source-id: 630d187ade68af1bf9db95466d035701062a1326

facebook/fbtorch