Clear in exit command

clears screen if application is terminated

project/Core/Src/cmd.c

@@ -139,6 +139,8 @@ static err_t echo_recv(void* arg, struct tcp_pcb* pcb, struct pbuf* p, err_t err
 
             check = 1;
         } else if (strncmp(tcp_buffer, "exit", 4) == 0) {
+            lcd_clear_images();
+            lcd_clear_text();
             echo_close(pcb);
             check = 1;
         }