Version 2 of my Sonoff Light Switch
This version does not need a seperate circuit board for the buttons, instead it uses the Sonoff's button connected to GIPO 0.
A video showing the overview of this code in action can be found here: https://www.youtube.com/watch?v=OK1kWAeawQA
You can download the .stl files here: https://www.thingiverse.com/thing:2632463
This is a video showing how to assemble it: https://www.youtube.com/watch?v=lnv1YRf7uRA
To install v2 in the wall (replacing an existing switch) see v1's video here: https://youtu.be/XgzF7lwwa0A?t=2m44s
For Refference, you can find the files for v1 following the links below.