[NEW PORT] comms/py-esptool: Utility to communicate with Espressif ESP8266 & ESP32 chips

A Python-based, open source, platform independent, utility to communicate
with the ROM bootloader in Espressif ESP8266 & ESP32 chips.

WWW: https://github.com/espressif/esptool

Reviewed by: koobs, mat
Approved by: koobs (mentor)
Differential Revision: https://reviews.freebsd.org/D16483