add ble_lywsd03mmc

[dhalbert]

BLE support for Xiaomi thermometer/hygrometer. This is for the factory firmware. There is also an open-source firmware load ("ATC") that will be a separate library.
https://www.adafruit.com/product/4881. Not yet in stock, but others found this library and are using it with their separately-purchased sensors, so we should release it.

[askpatrickw]

This looks identical to other add module merges with the exception of the lack of a docs link. I assume the docs will come when the product releases, so approving.

[kattni]

@dhalbert You need to add this to the library list in the docs folder. Take a look at it to get the format needed. Please let me know if you need assistance.

[dhalbert]

@kattni Thanks for reminding me. I also removed the word "Service" from a few other libs in there, because the libraries are not really just "Services", or what they are supporting is not exactly a Service.

[kattni]

Thanks @dhalbert!