output_node_prefix is different from output_prefix with suffix from 0-n

[lhdgriver]

132 for i in range(num_output):
133     pred_node_names[i] = args.output_node_prefix+str(i)  # Here 
134     pred[i] = tf.identity(net_model.outputs[i], name=pred_node_names[i])
135 print('output nodes names are: ', pred_node_names)

Say I set the output_node_prefix to 'value', then the actual output_node_name is 'value0', which is strange. I know the code is written to support multi-output scenarios, maybe we can "when the num_output is 1, there is no suffix, otherwise, we will use suffix". So when the num_output is 1, the output_node_name will be 'value', when there's many outputs, it will be 'value0', 'value1' ... 'value12', ...

If the idea is acceptable, I'd like to submit a pull request.