Validator to leader (#1303)

* Add check in window_service to exit in checks for leader rotation, and propagate that service exit up to fullnode

* Added logic to shutdown Tvu once ReplicateStage finishes

* Added test for successfully shutting down validator and starting up leader

* Add test for leader validator interaction

* fix streamer to check for exit signal before checking socket again to prevent busy leaders from never returning

* PR comments - Rewrite make_consecutive_blobs() function, revert genesis function change

src/replicator.rs

@@ -12,13 +12,13 @@ use std::time::Duration;
 use store_ledger_stage::StoreLedgerStage;
 use streamer::BlobReceiver;
 use window;
-use window_service::window_service;
+use window_service::{window_service, WindowServiceReturnType};
 
 pub struct Replicator {
     ncp: Ncp,
     fetch_stage: BlobFetchStage,
     store_ledger_stage: StoreLedgerStage,
-    t_window: JoinHandle<()>,
+    t_window: JoinHandle<Option<WindowServiceReturnType>>,
     pub retransmit_receiver: BlobReceiver,
 }