Added missing parameters (#237)

* Added missing parameters

added missing distributed_backend parameter and added the parameter to step 4 Init Trainer.

* Update single_gpu_node_dp_template.py

Author: TheStoneMX

examples/new_project_templates/single_gpu_node_dp_template.py

@@ -71,6 +71,7 @@ def main(hparams):
         checkpoint_callback=checkpoint,
         early_stop_callback=early_stop,
         gpus=hparams.gpus,
+        distributed_backend=hparams.dist_backend,
     )
 
     # ------------------------
@@ -94,6 +95,8 @@ def main(hparams):
     parent_parser.add_argument('--gpus', type=str, default='-1',
                                help='how many gpus to use in the node.'
                                     ' value -1 uses all the gpus on the node')
+    parent_parser.add_argument('--dist_backend', type=str, default='dp',
+                               help='When using multiple GPUs set Trainer(distributed_backend=dp) (or ddp)')
     parent_parser.add_argument('--test_tube_save_path', type=str, default=test_tube_dir,
                                help='where to save logs')
     parent_parser.add_argument('--model_save_path', type=str, default=checkpoint_dir,