Added user reference to api doc
Added user reference to api doc

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