Add SimpleIO and ESP libraries to README#6

Merged

kattni merged 3 commits intoadafruit:masterfrom

brentru:add-deps-to-readme

Jan 8, 2020

Commits on Apr 15, 2019

add simpleio and ESP managers to README deps
brentru
committed
fix link
brentru
committed

Commits on Jul 16, 2019

remove Atcontrol from readme
brentru
committed