remove matplotlib from predict.py

recognize_digits/predict.py

@@ -13,7 +13,6 @@
 # limitations under the License.
 """Usage: predict.py -c CONF -d DATA -m MODEL
 
-
 Arguments:
     CONF        train conf
     DATA        MNIST Data
@@ -29,7 +28,6 @@ Options:
 import os
 import sys
 from docopt import docopt
-import matplotlib.pyplot as plt
 import numpy as np
 
 from py_paddle import swig_paddle, DataProviderConverter