Now, register_view_op_c_code works exactly like for `DeepCopyOp`. There is no need to mention `register_OutputGuard_c_code` anymore. The warning does not apply now that we can specify which C code to register.

I would remove that note entirely, but add the same instructions as for `register_deep_copy_op_c_code`, like:
"As for `register_deep_copy_op_c_code`, in your C code, you should use `%(iname)s` and `%(oname)s` to represent
 the C variable names of the ViewOp input and output
respectively. See an example for the type ``CudaNdarrayType`` (GPU
array) in the file `theano/sandbox/cuda/type.py`."