fixed the num epochs for imagenet

cnn/train_imagenet.py

@@ -27,7 +27,7 @@
 parser.add_argument('--weight_decay', type=float, default=3e-5, help='weight decay')
 parser.add_argument('--report_freq', type=float, default=100, help='report frequency')
 parser.add_argument('--gpu', type=int, default=0, help='gpu device id')
-parser.add_argument('--epochs', type=int, default=1000, help='num of training epochs')
+parser.add_argument('--epochs', type=int, default=250, help='num of training epochs')
 parser.add_argument('--init_channels', type=int, default=48, help='num of init channels')
 parser.add_argument('--layers', type=int, default=14, help='total number of layers')
 parser.add_argument('--auxiliary', action='store_true', default=False, help='use auxiliary tower')