Remove log macros and fix log node prefix

[chenyukang]

There are two drawbacks for #120

1. we're losing source file and line number in log event
2. we macros don't support all argument format: https://docs.rs/tracing/latest/tracing/macro.info.html

There are several methods to propagate the span to spawned tasks:

1. instrument when using tokio spawn or actor span:

Actor::spawn_linked(...).instrument(span).await;

2. instrument with macors for a function

#[tracing::instrument(name = "Actor", skip(self, myself, args), fields(id = crate::get_node_prefix()))]
async fn pre_start(
        &self,
        myself: ActorRef<Self::Msg>,
        args: Self::Arguments,
    ) -> Result<Self::State, ActorProcessingErr> {
...
}

This PR use a trivial hack to achieve it, I think it's more general since developers may forget to set instrument for actors.