安卓系统实现多网络共存，可独立接入外部网络

有些场景下需要多网共存，使用网络聚合进行提升网速。而在Android系统源码上默认是不支持多网同时共存且能独立上外网的。所以需要进行定制修改

修改如下：

1.修改main 表优先级到9999， 作用：eth1 wlan0 访问内网

2.不去teardown 低分数网线

3.修改wifi为70分，以太网为60分，4G为50分

diff --git a/server/RouteController.cpp b/server/RouteController.cpp
index ba305e6..d38aec5 100644
--- a/server/RouteController.cpp
+++ b/server/RouteController.cpp
@@ -721,6 +721,18 @@ int RouteController::configureDummyNetwork() {
     return 0;
 }
 
+// Add a new rule to look up the 'main' table, with the same selectors as the "default network"
+// rule, but with a lower priority. We will never create routes in the main table; it should only be
+// used for directly-connected routes implicitly created by the kernel when adding IP addresses.
+// This is necessary, for example, when adding a route through a directly-connected gateway: in
+// order to add