Sync pirate wallet every 30 seconds instead of 60, to match behaviour of official wallet.

src/main/java/org/qortal/controller/PirateChainWalletController.java

@@ -65,7 +65,7 @@ public class PirateChainWalletController extends Thread {
                 }
 
                 // Rate limit sync attempts
-                Thread.sleep(60000);
+                Thread.sleep(30000);
 
                 // Save wallet if needed
                 Long now = NTP.getTime();