Add small clarification on how to power Zyxel PMG3000-D20B - #417

Unexpected input(s) 'if', valid inputs are ['entryPoint', 'args', 'to', 'token', 'message', 'message_file', 'socks5', 'photo', 'document', 'sticker', 'audio', 'voice', 'location', 'venue', 'video', 'debug', 'format', 'disable_web_page_preview', 'disable_notification']