update MinSaver function in saver.py (#212)

* update MinSaver function in saver.py

* fix linting and style

tensorpack/callbacks/saver.py

@@ -5,6 +5,7 @@
 import tensorflow as tf
 import os
 import shutil
+import glob
 
 from .base import Callback
 from ..utils import logger
@@ -122,10 +123,14 @@ class MinSaver(Callback):
             raise RuntimeError(
                 "Cannot find a checkpoint state. Do you forget to use ModelSaver?")
         path = ckpt.model_checkpoint_path
+
         newname = os.path.join(logger.LOG_DIR,
                                self.filename or
-                               ('max-' if self.reverse else 'min-' + self.monitor_stat + '.tfmodel'))
-        shutil.copy(path, newname)
+                               ('max-' if self.reverse else 'min-' + self.monitor_stat))
+        files_to_copy = glob.glob(path + '*')
+        for file_to_copy in files_to_copy:
+            shutil.copy(file_to_copy, file_to_copy.replace(path, newname))
+        #shutil.copy(path, newname)
         logger.info("Model with {} '{}' saved.".format(
             'maximum' if self.reverse else 'minimum', self.monitor_stat))