Pad out the segment identifier for Swift segments and change test back to string comparison

Makes us follow the docs closer

storage/swift.py

@@ -298,7 +298,7 @@ class SwiftStorage(BaseStorage):
   def _stream_upload_segment(self, uuid, offset, length, in_fp, storage_metadata, content_type):
     updated_metadata = copy.deepcopy(storage_metadata)
     segment_count = len(updated_metadata[_SEGMENTS_KEY])
-    segment_path = '%s/%s/%s' % (_SEGMENT_DIRECTORY, uuid, segment_count)
+    segment_path = '%s/%s/%s' % (_SEGMENT_DIRECTORY, uuid, '%09d' % segment_count)
 
     # Track the number of bytes read and if an explicit length is specified, limit the
     # file stream to that length.

storage/test/test_swift.py

@@ -84,7 +84,7 @@ class FakeSwift(object):
         if ('container-name/' + key).startswith(prefix):
           new_contents.append((key, value['content']))
 
-      new_contents.sort(key=lambda value: int(value[0].split('/')[-1]))
+      new_contents.sort(key=lambda value: value[0])
 
       data = dict(data)
       data['content'] = ''.join([nc[1] for nc in new_contents])