adding save checkpoint and loading in examples

examples/run_squad.py

@@ -690,7 +690,7 @@ def main():
                         help="Bert pre-trained model selected in the list: bert-base-uncased, "
                              "bert-large-uncased, bert-base-cased, bert-base-multilingual, bert-base-chinese.")
     parser.add_argument("--output_dir", default=None, type=str, required=True,
-                        help="The output directory where the model checkpoints will be written.")
+                        help="The output directory where the model checkpoints and predictions will be written.")
 
     ## Other parameters
     parser.add_argument("--train_file", default=None, type=str, help="SQuAD json for training. E.g., train-v1.1.json")