feat(gpsrelaysentinel): 前台服务通知添加GPS数据计数值

- 添加mGpsCount计数器统计GPS数据接收次数
- 每次onLocationChanged时计数器自增
- 通知栏实时显示GPS数据计数值（Count: x）
- 计数包含在通知内容中：经纬度 | Count: x

gpsrelaysentinel/src/main/java/cc/winboll/studio/gpsrelaysentinel/MainService.java

@@ -28,6 +28,7 @@ public class MainService extends Service {
     private static final int NOTIFICATION_ID = 1;
     private static final String PREF_NAME = "gps_relay_service_prefs";
     private static final String KEY_SERVICE_ENABLED = "service_enabled";
+    private int mGpsCount = 0;
 
     @Override
     public void onCreate() {
@@ -67,6 +68,7 @@ public class MainService extends Service {
         mLocationListener = new LocationListener() {
             @Override
             public void onLocationChanged(Location location) {
+                mGpsCount++;
                 String gpsInfo = "Lat: " + location.getLatitude() + ", Lng: " + location.getLongitude();
                 LogUtils.d(TAG, "Location changed: " + gpsInfo);
                 updateNotification(gpsInfo);
@@ -129,7 +131,7 @@ public class MainService extends Service {
 
     private void updateNotification(String gpsInfo) {
         if (mNotificationBuilder != null) {
-            mNotificationBuilder.setContentText(gpsInfo);
+            mNotificationBuilder.setContentText(gpsInfo + " | Count: " + mGpsCount);
             mNotificationManager.notify(NOTIFICATION_ID, mNotificationBuilder.build());
         }
     }