fixed issue in IRC backend with nick length (max 16 chars)
fixed issue in IRC backend with nick length (max 16 chars)

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