* Added a 'RivWebPyError' exception type to the 'rivwebpyapi' API.
* Modified the 'rivwebpyapi.AddCart()' method to return a single
dictionary.
* Modified the 'rivwebpyapi.AddCut()' method to return a single
dictionary.
* Modified the 'rivwebpyapi.AudioInfo()' method to return a single
dictionary.
* Modified the 'rivwebpyapi.AssignSchedCode()' method to return a
single dictionary.
* Modified the 'rivwebpyapi.AudioStore()' method to return a single
dictionary.
* Modified the 'rivwebpyapi.ListCart()' method to return a single
dictionary.
* Modified the 'rivwebpyapi.ListCut()' method to return a single
dictionary.
* Modified the 'rivwebpyapi.ListGroup()' method to return a single
dictionary.
* Modified the 'rivwebpyapi.ListSystemSettings()' method to return a
single dictionary.
Signed-off-by: Fred Gleason <fredg@paravelsystems.com>