code updated on Github for Arduino 1.8.15 compatibility.

The problem turned out to be the BLE library uses a lot of memory, so much so when the Webpage, also being served by this sketch, is activated the ESP32 ran out of memory.   For whatever reason, this did not turn up when testing with 1.8.14.

In any case, the code is now updated on Github to correct for this.

Also, required is the simple patch described here: https://github.com/T-vK/ESP32-BLE-Keyboard/pull/54