优化etcd发现服务，支持记录附加信息rpc

rpc/origindiscover.proto

@@ -0,0 +1,35 @@
+syntax = "proto3";
+package rpc;
+option go_package = ".;rpc";
+
+message NodeInfo{
+    string NodeId = 1;
+    string ListenAddr  = 2;
+    uint32 MaxRpcParamLen = 3;
+    bool Private = 4;
+	bool Retire = 5;
+    repeated string PublicServiceList = 6;
+}
+
+//Client->Master
+message ServiceDiscoverReq{
+    NodeInfo nodeInfo = 1;
+}
+
+//Master->Client
+message SubscribeDiscoverNotify{
+    string MasterNodeId = 1;
+    bool IsFull = 2;
+    string DelNodeId    = 3;
+    repeated NodeInfo nodeInfo = 4;
+}
+
+
+//Client->Master
+message NodeRetireReq{
+    NodeInfo nodeInfo = 1;
+}
+
+//Master->Client
+message Empty{
+}