fix(electro-webvr): Fix boolean --opt values
fix(three-vr-multires): Clear canvas before drawing
fix(three-vr-multires): Correct debugging comment
fix(present-simple): Fix div stacking order
fix(present-simple): CSS comment syntax
refactor(present-simple): Simplify block scope
feat(present-simple): Add divs behind the layers
Change present-simple div API
Add vive-camera-stream
Add ew-vive-camera-video