Update README.md for better description of the different variants

[KingKeule]

I bought a DSTIKE WiFi Deauth Detector.
When I wanted to flash the stick myself, it was difficult for me to understand which of the configuration (code) provided here was the right one for me, because I could not / would not open the usb stick and in the sales description was nothing specific.

It would be very helpful if more or at least the following information was documented:
There are different code examples, which are for different boards with different hardware (RGB LED, NeoPixel RGB LED, Buzzzer, ...).
For all variants of the DSTIKE WiFi Deauth Detector "deauth_detector_buzzer", "deauth_detector_buzzer_neopixel" and "deauth_detector_neopixel" are appropriate. Depending on the desired function e.g. "LED only" please use "deauth_detector_neopixel".