Fixed missing import.

rstevaluation/rstevaluation/files.py

@@ -7,6 +7,7 @@ import csv
 import json
 import operator
 import os
+import shutil
 
 import nptdms
 import numpy as np
@@ -429,5 +430,5 @@ def check_tdms(file_list, config):
             file_path = os.path.join(config['paths']['path_in'], file_name)
             new_path = os.path.join(raw_folder, file_name)
             shutil.move(file_path, new_path)
-            new_file_path = downsample_file(new_path)
+            new_file_path = rstdat.downsample_file(new_path)
             shutil.move(new_file_path, file_path)