fixed broadcast(message) in sandbox::helpers
fixed broadcast(message) in sandbox::helpers


Former-commit-id: 6e151ee5c05ffbf08374b5e233b06331488ad51b
alekseysidorov/exonum,exonum/exonum,exonum/exonum,exonum/exonum,alekseysidorov/exonum,alekseysidorov/exonum,exonum/exonum,alekseysidorov/exonum