improved gsm validator to attempt reading file in n different encodings
improved gsm validator to attempt reading file in n different encodings

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