WX initialize block - if return to Term & Programming on WX, return to DI = WX Socket

[AndyLindsay]

The WX initialize block defaults to mode: Term & Programming no WX and DI: WX Socket. When mode is changed, the DO pin appears, and I/O pins other than P30 and P31 can be chosen. When the mode is set back to Term & Programming on WX after using one of the other modes, the DI and DO pins are still visible and might not be 30 and 31. It would be better to have them return DI to WX Socket and have DO disappear again.