simplify tox testing docs
simplify tox testing docs

caktus/rapidsms,ehealthafrica-ci/rapidsms,catalpainternational/rapidsms,peterayeni/rapidsms,eHealthAfrica/rapidsms,caktus/rapidsms,lsgunth/rapidsms,catalpainternational/rapidsms,ehealthafrica-ci/rapidsms,lsgunth/rapidsms,lsgunth/rapidsms,eHealthAfrica/rapidsms,caktus/rapidsms,eHealthAfrica/rapidsms,peterayeni/rapidsms,lsgunth/rapidsms,catalpainternational/rapidsms,ehealthafrica-ci/rapidsms,peterayeni/rapidsms,catalpainternational/rapidsms,peterayeni/rapidsms