message: reverse the change of dcn.json
diff: "lr_policy": "fixed",
  "display": 1000,
  "max_iter": 300000,
  - "gpu": [0,1,2,3],
  + "gpu": [0],
  "batchsize": 512,
  "snapshot": 10000000,
  "snapshot_prefix": "./",
  {
  "name": "data",
  "type": "Data",
  - "source": "/gpfs/fs1/zehuanw/dataset/dcn/file_list.txt",
  - "eval_source": "/gpfs/fs1/zehuanw/dataset/dcn/file_list_test.txt",
  + "source": "./file_list.txt",
  + "eval_source": "./file_list_test.txt",
  "check": "Sum",
  "label": {
  "top": "label",
  