Implement graceful shutdown (#2812)

* Remove stop status mutex
* remove some deadlocks
* Rewrite stop channel handling
* fix deadlock in peers object
* add missing test fixes

src/bin/tui/status.rs

@@ -199,6 +199,7 @@ impl TUIStatusListener for TUIStatusView {
 					};
 					format!("Downloading blocks: {}%, step 4/4", percent)
 				}
+				SyncStatus::Shutdown => "Shutting down, closing connections".to_string(),
 			}
 		};
 		/*let basic_mining_config_status = {

src/bin/tui/ui.rs

@@ -173,8 +173,10 @@ impl Controller {
 			while let Some(message) = self.rx.try_iter().next() {
 				match message {
 					ControllerMessage::Shutdown => {
-						server.stop();
 						self.ui.stop();
+						println!("Shutdown in progress, please wait");
+						server.stop();
+						return;
 					}
 				}
 			}