change error message explicitly referenced from test code(!?)
change error message explicitly referenced from test code(!?)

geotagx/geotagx-pybossa-archive,proyectos-analizo-info/pybossa-analizo-info,jean/pybossa,harihpr/tweetclickers,geotagx/pybossa,Scifabric/pybossa,CulturePlex/pybossa,stefanhahmann/pybossa,jean/pybossa,stefanhahmann/pybossa,PyBossa/pybossa,geotagx/geotagx-pybossa-archive,geotagx/pybossa,CulturePlex/pybossa,Scifabric/pybossa,geotagx/geotagx-pybossa-archive,OpenNewsLabs/pybossa,proyectos-analizo-info/pybossa-analizo-info,harihpr/tweetclickers,inteligencia-coletiva-lsd/pybossa,PyBossa/pybossa,inteligencia-coletiva-lsd/pybossa,geotagx/geotagx-pybossa-archive,proyectos-analizo-info/pybossa-analizo-info,CulturePlex/pybossa,OpenNewsLabs/pybossa,geotagx/geotagx-pybossa-archive