set correct max id on dbh

src/de/tudarmstadt/informatik/hostage/persistence/HostageDBOpenHelper.java

@@ -217,7 +217,7 @@ public class HostageDBOpenHelper extends SQLiteOpenHelper {
                 editor.putString("CURRENT_DEVICE_IDENTIFIER", thisDevice.getDeviceID());
                 editor.commit();
                 thisDevice.setLast_sync_timestamp(0);
-                thisDevice.setHighest_attack_id(-1);
+                thisDevice.setHighest_attack_id(attack_id-1);
                 ArrayList<SyncDevice> devices = new ArrayList<SyncDevice>();
                 devices.add(thisDevice);
                 this.insertSyncDevices(devices);