Fix number of arguments on overriden method.
Fix number of arguments on overriden method.

OpenNewsLabs/pybossa,stefanhahmann/pybossa,OpenNewsLabs/pybossa,jean/pybossa,Scifabric/pybossa,inteligencia-coletiva-lsd/pybossa,geotagx/pybossa,Scifabric/pybossa,PyBossa/pybossa,PyBossa/pybossa,jean/pybossa,inteligencia-coletiva-lsd/pybossa,geotagx/pybossa,stefanhahmann/pybossa