epee: close connection when the peer has done so

This fixes rapid reconnections failing as the peer hasn't yet
worked out the other side is gone, and will reject "duplicate"
connections until a timeout.

contrib/epee/include/net/abstract_tcp_server2.inl

@@ -410,7 +410,12 @@ PRAGMA_WARNING_DISABLE_VS(4355)
       else
       {
         _dbg3("[sock " << socket().native_handle() << "] peer closed connection");
-        if (m_ready_to_close)
+        bool do_shutdown = false;
+        CRITICAL_REGION_BEGIN(m_send_que_lock);
+        if(!m_send_que.size())
+          do_shutdown = true;
+        CRITICAL_REGION_END();
+        if (m_ready_to_close || do_shutdown)
           shutdown();
       }
       m_ready_to_close = true;
@@ -470,6 +475,7 @@ PRAGMA_WARNING_DISABLE_VS(4355)
       {
         MERROR("SSL handshake failed");
         boost::interprocess::ipcdetail::atomic_write32(&m_want_close_connection, 1);
+        m_ready_to_close = true;
         bool do_shutdown = false;
         CRITICAL_REGION_BEGIN(m_send_que_lock);
         if(!m_send_que.size())