Mocha: Convert torch model to/from caffe model easily

Caffe: load with Python.
Torch: load with Lua.

Q. How to connect Python & Lua code?
A. We don't need directly interact Python code with Lua code, which is complex. We use intermediate file exchange, the model parameters are saved to disk layer by layer as .npy file, and then loaded to caffe/torch separately.

TODO:

• Caffe split layer -> Torch ConcatTable
• PReLU
• More tests