fix issues with Python 3.5 about puncover HOT 1 CLOSED

$ python3.5 -m nose
.................F.....................................
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FAIL: test_enhance_file_elements (tests.test_collector.TestCollector)
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Traceback (most recent call last):
  File "/Users/tyler/dev/junk/puncover/tests/test_collector.py", line 415, in test_enhance_file_elements
    self.assertListEqual([aa, ab, b], crf)
AssertionError: Lists differ: [{'co[18 chars]s': [], 'name': 'a', 'collapsed_name': 'a/a', [6996 chars]'b'}] != [{'co[18 chars]s': [{'collapsed_sub_folders': [], 'name': 'a'[6996 chars]/b'}]

First differing element 0:
{'col[17 chars]s': [], 'name': 'a', 'collapsed_name': 'a/a', [2565 chars]a/a'}
{'col[17 chars]s': [{'collapsed_sub_folders': [], 'name': 'a'[1715 chars] 'b'}

Diff is 28182 characters long. Set self.maxDiff to None to see it.

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Ran 55 tests in 0.196s