Fix broken import in WN script (#650)

Author: drmarkwslater

python/Ganga/GPIDev/Lib/File/OutputFileManager.py

@@ -162,7 +162,7 @@ def getWNCodeForOutputSandbox(job, files, jobid):
                 patternsToSandbox.append(outputFile.namePattern)
 
     insertScript = """\n
-from Ganga.Utility.files import recursive_copy
+from files import recursive_copy
 import glob
 import os