Changed num epochs for training

examples/A3C-Gym/train-atari.py

@@ -276,7 +276,7 @@ def train():
         session_creator=sesscreate.NewSessionCreator(config=get_default_sess_config(0.5)),
         steps_per_epoch=STEPS_PER_EPOCH,
         session_init=SmartInit(args.load),
-        max_epoch=15,
+        max_epoch=12,
     )
     trainer = SimpleTrainer() if num_gpu == 1 else AsyncMultiGPUTrainer(train_tower)
     launch_train_with_config(config, trainer)