text: Title: Encoding of pytest test names is not preserved
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  Hi !
  
  #### I'm submitting a ... 
    - [x] bug report
    - [ ] feature request
    - [ ] support request => Please do not submit support request here, see note at the top of this template.
  
  #### What is the current behavior?
  
  Test names are not properly utf8-encoded in results files.
  
  #### If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem
  
  Here is a very simple test. 
  
  ```python
  # test_allure.py
  
  def test_musée(self):
      assert False
  ```
  
  JSON output:
  ```json
  {"name": "test_musÃ©e", "status": "failed", "statusDetails": {"message": "AssertionError: assert False", "trace": "E   assert False"}, "start": 1527000563172, "stop": 1527000563173, "uuid": "80c6f937-6366-4a1c-a194-f159517e1e4a", "historyId": "b9238153ea1ae00f41b1b2da19fba81e", "fullName": "test_allure#test_musÃ©e", "labels": [{"name": "host", "value": "adrien-XPS"}, {"name": "thread", "value": "9176-MainThread"}, {"name": "framework", "value": "pytest"}, {"name": "language", "value": "cpython3"}, {"name": "package", "value": "test_allure"}]}
  ```
  
  #### What is the expected behavior?
  
  UTF8 names are preserved.
  
  
  #### Please tell us about your environment:
  
  - Allure version:        2.6.0
  - Test framework:        pytest@3.5.1
  - Allure adaptor:        allure-pytest@2.3.3b1
  
  #### Other information 
  I suppose that [`escape_name`](https://github.com/allure-framework/allure-python/blob/master/allure-pytest/src/utils.py#L102) function is to blame here. But I don't really understand how it is used and why. 
  