Update to WiFi clock Readme

[ulwur]

Hi!

First of all, thanks for a great project!

Regarding the issue with new displays from Aliexpress, it might be a good idea to describe the issue that occurs, and change the text to indicate that the issue is fixed by 2DOM by now.

I spent 4 hours today trying different settings on the DIP-switches on the TinyPico adapter board and in the code before I stumbled upon the issue in 2DOM's github for the PxMatrix project, and from there realized this was the same problem you hinted in the readme.