* fix(transport): reconnect lazy connections after first failure
Channels created with lazy connections never try to reconnect if the
first connection attempt fails. This is because `Reconnect` returns
`Poll::Ready(Err)` on poll_ready and the service is considered dead.
This change passes a flag to Reconnect to signal if the connection
is intended to be lazy, in which case reconnect returns the error on
the next call.
fixes#452
