add tpu_forwarding, simplify ClusterInfo::new() from Result<Self> to Self

src/lib.rs

@@ -77,6 +77,7 @@ pub mod system_transaction;
 pub mod thin_client;
 pub mod token_program;
 pub mod tpu;
+pub mod tpu_forwarder;
 pub mod transaction;
 pub mod tvu;
 pub mod vote_program;