add BytestreamS5BCannotConnect and use it in BytestreamSIFallbackS5CannotConnect
add BytestreamS5BCannotConnect and use it in BytestreamSIFallbackS5CannotConnect

mlundblad/telepathy-gabble,jku/telepathy-gabble,community-ssu/telepathy-gabble,community-ssu/telepathy-gabble,Ziemin/telepathy-gabble,jku/telepathy-gabble,jku/telepathy-gabble,mlundblad/telepathy-gabble,Ziemin/telepathy-gabble,community-ssu/telepathy-gabble,Ziemin/telepathy-gabble,mlundblad/telepathy-gabble,Ziemin/telepathy-gabble,community-ssu/telepathy-gabble