configure cloudooo by URL in default preference

Since !306 (merged) we have configured system preference to use cloudoo from the Slapos SR, but this configuration was still old style configuration setting host / port.

It caused a test to fail

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FAIL: test_01_PreferenceSetup (testIngestion.TestIngestion)
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Traceback (most recent call last):
  File "/srv/slapgrid/slappart7/srv/testnode/aai/soft/f030becfa6e3878c62ccb9bccc43a291/parts/erp5/Products/ERP5OOo/tests/testIngestion.py", line 1048, in test_01_PreferenceSetup
    self.assertEqual(preference_tool.getPreferredOoodocServerAddress(), conversion_dict['hostname'])
AssertionError: 'erp5-cloudooo' != 'localhost'

and that was a problem with the test, we don't have to care about getPreferredOoodocServerAddress, as only URL matters now (it was just working because both were set to localhost).