Keep the scale when exporting the mesh.

SculptGL normalize the mesh at loading. Now we keep the scale difference
and apply it back when we export the mesh.
Add upload to Verold button.
Add success message on verold upload + fix crease adaptive.
Add success message on verold upload + fix crease adaptive.
Add sketchfab upload.
Merge branch 'master' of https://github.com/stephomi/sculptgl

Conflicts:
	build/sculptgl/sculptgl.min.js
Let's close these 2 folds :p.
Let's get rid of this hack.
Refactor project/unproject.
Remove useless test.
Update build.
Add binary and ascii import STL.
Update meta
add drag.
Fix brush tool, no more flatten+brush for the brush tool.
prevent zoom on whole document using touch
prevent touch scroll on whole page
add single touch support
- render using requestAnimationFrame instead on each user event
- optimisation: upload buffer to gpu only once a frame