Add a constructor method for Backend
Add a constructor method for Backend

unicefuganda/edtrac,lsgunth/rapidsms,eHealthAfrica/rapidsms,caktus/rapidsms,lsgunth/rapidsms,peterayeni/rapidsms,ehealthafrica-ci/rapidsms,lsgunth/rapidsms,ehealthafrica-ci/rapidsms,peterayeni/rapidsms,catalpainternational/rapidsms,dimagi/rapidsms,unicefuganda/edtrac,rapidsms/rapidsms-core-dev,catalpainternational/rapidsms,caktus/rapidsms,eHealthAfrica/rapidsms,peterayeni/rapidsms,rapidsms/rapidsms-core-dev,unicefuganda/edtrac,peterayeni/rapidsms,catalpainternational/rapidsms,ken-muturi/rapidsms,dimagi/rapidsms,dimagi/rapidsms-core-dev,lsgunth/rapidsms,ehealthafrica-ci/rapidsms,ken-muturi/rapidsms,dimagi/rapidsms-core-dev,eHealthAfrica/rapidsms,ken-muturi/rapidsms,caktus/rapidsms,catalpainternational/rapidsms