Update libraries.rst with ESP-NOW (#5322)
Update libraries.rst with ESP-NOW (#5322)

Fixes #2227
esp8266/Arduino,Lan-Hekary/Arduino,sticilface/Arduino,sticilface/Arduino,Lan-Hekary/Arduino,Lan-Hekary/Arduino,esp8266/Arduino,esp8266/Arduino,Lan-Hekary/Arduino,sticilface/Arduino,Lan-Hekary/Arduino,esp8266/Arduino,esp8266/Arduino,sticilface/Arduino,sticilface/Arduino