Drive: fix failing IT jobs under Windows

For example:

• in https://qa.nuxeo.org/jenkins/job/IT-nuxeo-drive-master-windows/192/consoleFull:

  18:41:27   File "C:\Jenkins\workspace\IT-nuxeo-drive-master-windows\nuxeo-drive-client\nxdrive\tests\test_integration_synchronization.py", line 871, in test_synchronize_deep_folders
  18:41:27     self.assertTrue(local.exists(expected_folder_path))
  18:41:27 AssertionError: False is not true
  ...
  00:37:52 nxdrive.synchronizer: TRACE: Client offline in synchronization loop: timed out
  00:37:52 nxdrive.synchronizer: TRACE: Traceback of ignored network error:
  00:37:52 Traceback (most recent call last):
  00:37:52   File "nuxeo-drive-client\nxdrive\synchronizer.py", line 1315, in update_synchronize_server
  00:37:52   File "nuxeo-drive-client\nxdrive\synchronizer.py", line 1204, in _get_remote_changes
  00:37:52   File "nuxeo-drive-client\nxdrive\client\remote_file_system_client.py", line 250, in get_changes
  00:37:52   File "nuxeo-drive-client\nxdrive\client\base_automation_client.py", line 176, in execute
  00:37:52   File "C:\Python27\lib\urllib2.py", line 400, in open
  00:37:52     response = self._open(req, data)
  00:37:52   File "C:\Python27\lib\urllib2.py", line 418, in _open
  00:37:52     '_open', req)
  00:37:52   File "C:\Python27\lib\urllib2.py", line 378, in _call_chain
  00:37:52     result = func(*args)
  00:37:52   File "C:\Python27\lib\urllib2.py", line 1207, in http_open
  00:37:52     return self.do_open(httplib.HTTPConnection, req)
  00:37:52   File "C:\Python27\lib\urllib2.py", line 1180, in do_open
  00:37:52     r = h.getresponse(buffering=True)
  00:37:52   File "C:\Python27\lib\httplib.py", line 1030, in getresponse
  00:37:52     response.begin()
  00:37:52   File "C:\Python27\lib\httplib.py", line 407, in begin
  00:37:52     version, status, reason = self._read_status()
  00:37:52   File "C:\Python27\lib\httplib.py", line 365, in _read_status
  00:37:52     line = self.fp.readline()
  00:37:52   File "C:\Python27\lib\socket.py", line 447, in readline
  00:37:52     data = self._sock.recv(self._rbufsize)
  00:37:52 timeout: timed out
  

• in http://qa.nuxeo.org/jenkins/job/IT-nuxeo-drive-master-windows/188/consoleFull

  20:36:14   File "C:\Jenkins\workspace\IT-nuxeo-drive-master-windows\nuxeo-drive-client\nxdrive\tests\test_integration_synchronization.py", line 256, in test_binding_synchronization_empty_start
  20:36:14     (u'Folder 4', u'unknown'),
  20:36:14 AssertionError: Lists differ: [(u'File 5.txt', u'remotely_cr... != [(u'File 5.txt', u'locally_del...
  

• in https://qa.nuxeo.org/jenkins/job/IT-nuxeo-drive-master-windows/191/consoleFull or http://qa.nuxeo.org/jenkins/job/IT-nuxeo-drive-5.6.0-windows/420/consoleFull

  test_conflict_detection_and_renaming (nxdrive.tests.test_integration_synchronization.TestIntegrationSynchronization)
  ...
  21:15:33 Traceback (most recent call last):
  21:15:33   File "nuxeo-drive-client\nxdrive\synchronizer.py", line 1037, in synchronize
  21:15:33   File "nuxeo-drive-client\nxdrive\synchronizer.py", line 575, in synchronize_one
  21:15:33   File "nuxeo-drive-client\nxdrive\synchronizer.py", line 814, in _synchronize_conflicted
  21:15:33   File "nuxeo-drive-client\nxdrive\client\remote_file_system_client.py", line 147, in conflicted_name
  21:15:33   File "nuxeo-drive-client\nxdrive\client\base_automation_client.py", line 152, in execute
  21:15:33   File "C:\Python27\lib\json\__init__.py", line 243, in dumps
  21:15:33     return _default_encoder.encode(obj)
  21:15:33   File "C:\Python27\lib\json\encoder.py", line 207, in encode
  21:15:33     chunks = self.iterencode(o, _one_shot=True)
  21:15:33   File "C:\Python27\lib\json\encoder.py", line 270, in iterencode
  21:15:33     return _iterencode(o, 0)
  UnicodeDecodeError: 'utf8' codec can't decode byte 0x92 in position 22: invalid start byte