Add shallow cloning of messages on response to preserve out-of-band data.
Add shallow cloning of messages on response to preserve out-of-band
data.

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