Added feeler connections increasing good addrs in the tried table.

src/main.cpp

@@ -4973,6 +4973,12 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
 
     if (strCommand == NetMsgType::VERSION)
     {
+        // Feeler connections exist only to verify if address is online.
+        if (pfrom->fFeeler) {
+            assert(pfrom->fInbound == false);
+            pfrom->fDisconnect = true;
+        }
+
         // Each connection can only send one version message
         if (pfrom->nVersion != 0)
         {