Fixed busy-wait bug in Router.run().
Fixed busy-wait bug in Router.run().

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