[rendering] update build script#2113

Merged

rachel-fenichel merged 2 commits intoRaspberryPiFoundation:renderingfrom

samelhusseini:rendering_build

Nov 15, 2018

Commits on Nov 14, 2018

Update build to support custom rendering and add scratch blocks playground.
Sam El-Husseini
committed

Commits on Nov 15, 2018

PR feedback, renaming from scratch to 2018_rendering
Sam El-Husseini
committed