Super tiny RPC refactor (#1187)

* wip: mwake the request id optional

* make the request_id optional

* cleanup

* address clippy lints inside rpc

* WIP: Separate sent RPC events from received ones

* WIP: Separate sent RPC events from received ones

* cleanup

* Separate request ids from substream ids

* Make RPC's message handling independent of RequestIds

* Change behaviour RPC events to be more outside-crate friendly

* Propage changes across the network + router + processor

* Propage changes across the network + router + processor

* fmt

* "tiny" refactor

* more tiny refactors

* fmt eth2-libp2p

* wip: propagating changes

* wip: propagating changes

* cleaning up

* more cleanup

* fmt

* tests HOT fix

Co-authored-by: Age Manning <Age@AgeManning.com>

beacon_node/network/src/sync/mod.rs

@@ -9,3 +9,6 @@ mod range_sync;
 
 pub use manager::SyncMessage;
 pub use peer_sync_info::PeerSyncInfo;
+
+/// Type of id of rpc requests sent by sync
+pub type RequestId = usize;