Saving settings and local database on application exit

Fixes #55

src/main/java/envoy/client/ui/Startup.java

@@ -11,6 +11,7 @@ import javax.swing.JOptionPane;
 import envoy.client.Client;
 import envoy.client.Config;
 import envoy.client.LocalDB;
+import envoy.client.Settings;
 import envoy.client.util.EnvoyLog;
 import envoy.exception.EnvoyException;
 import envoy.schema.User;
@@ -126,5 +127,18 @@ public class Startup {
 				e.printStackTrace();
 			}
 		});
+		
+		// Save Settings and LocalDB on shutdown
+		Runtime.getRuntime().addShutdownHook(new Thread(() -> {
+			try {
+				logger.info("Saving local database...");
+				localDB.save();
+				logger.info("Saving settings...");
+				Settings.getInstance().save();
+			} catch (IOException e1) {
+				e1.printStackTrace();
+				logger.log(Level.WARNING, "Unable to save the messages", e1);
+			}
+		}));
 	}
 }