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.

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