Add a Pixel Editor to web interface

[sfranzyshen]

Add a graphical pixel editor to the web interface ... support gif animations for pattern playback

https://github.com/piskelapp/piskel
https://github.com/Convicted202/PixelShape

[sfranzyshen]

this might best be created and implemented in a "end user" project instead of in the core ... this would best be suited for the 8x8 pixel grid demo mentioned in #12