Fix checksum support to be compatible with Windows.

boto/s3/resumable_download_handler.py

 # Copyright 2010 Google Inc.
 #
 # Permission is hereby granted, free of charge, to any person obtaining a
 # copy of this software and associated documentation files (the
 # "Software"), to deal in the Software without restriction, including
 # without limitation the rights to use, copy, modify, merge, publish, dis-
 # tribute, sublicense, and/or sell copies of the Software, and to permit
 # persons to whom the Software is furnished to do so, subject to the fol-
 # lowing conditions:
 #
@@ skipping 202 matching lines @@
         fp.flush()
 
     def _check_final_md5(self, key, file_name):
         """
         Checks that etag from server agrees with md5 computed after the
         download completes. This is important, since the download could
         have spanned a number of hours and multiple processes (e.g.,
         gsutil runs), and the user could change some of the file and not
         realize they have inconsistent data.
         """
-        fp = open(file_name, 'r')
+        fp = open(file_name, 'rb')
         if key.bucket.connection.debug >= 1:
             print 'Checking md5 against etag.'
         hex_md5 = key.compute_md5(fp)[0]
         if hex_md5 != key.etag.strip('"\''):
             file_name = fp.name
             fp.close()
             os.unlink(file_name)
             raise ResumableDownloadException(
                 'File changed during download: md5 signature doesn\'t match '
                 'etag (incorrect downloaded file deleted)',
@@ skipping 110 matching lines @@
                 key.close()
             except httplib.IncompleteRead:
                 pass
 
             sleep_time_secs = 2**progress_less_iterations
             if debug >= 1:
                 print('Got retryable failure (%d progress-less in a row).\n'
                       'Sleeping %d seconds before re-trying' %
                       (progress_less_iterations, sleep_time_secs))
             time.sleep(sleep_time_secs)