title: how to fix this cudnn and torch error
body: <p>I run the torch <code>./test.sh</code>,and get error like these:</p>
  
  <pre><code>Found Environment variable CUDNN_PATH = /usr/local/cuda-8.0/lib64/libcudnn.so.6
  /home/whj/torch/install/bin/luajit: /home/whj/torch/install/share/lua/5.1/cudnn/ffi.lua:1618: These bindings are for CUDNN 5.x (5005 &lt;= cudnn.version &gt; 6000) , while the loaded CuDNN is version: 6020  
  Are you using an older or newer version of CuDNN?
  </code></pre>
  
  <p>My cuda is 8.0 and already move libcudnn.so.6 into its folder, how can I fix error above. 
  At the beginning, it just reports error like couldn't find libcudnn.so.6, no such file etc, and then I add the <code>export CUDNN_PATH="/usr/local/cuda-8.0/lib64/libcudnn.so.6$CUDNN_PATH"</code> in /.bashrc and reboot, it change to error above.</p>