Test that a data-node does not start if configuration specifies
   * incorrect URI scheme in data directory.
   * Test that a data-node starts if data directory is specified as
   * URI = "file:///path" or as a non URI path.
Test that a data-node does not start if configuration specifies
   * incorrect URI scheme in data directory.
   * Test that a data-node starts if data directory is specified as
   * URI = "file:///path" or as a non URI path. | TestDatanodeConfig.java