Merge branch 'develop' into test

app/src/main/java/com/bgycc/smartcanteen/server/websocket/MainWebSocket.java

@@ -110,10 +110,11 @@ public class MainWebSocket extends WebSocketClient {
             }
 
             private void doHeartbeat() {
-                // 每10分钟发一次心跳包给后端
+                // 每3分钟发一次心跳包给后端
+                // 原为10分钟一次，现改为3分钟一次以方便后台预警功能
                 sAutoCheckCount -= 2;
                 if (sAutoCheckCount < 0) {
-                    sAutoCheckCount = 10 * 60;
+                    sAutoCheckCount = 3 * 60;
                     try {
                         JSONObject data = new JSONObject();
                         data.put(FieldEnum.equipmentId.name(), sDeviceSN);