- cosmetic and structural improvement to code editor
 * added experimental "toolbar" (non functional for now)
 * reorganized css & templates structure
 * cleaned up file tree view
 * overall clean up
- migrating three.js lib to latest (v56): lots of things broken
 These are all related to the migration, no error before
 * fixed picking
 * fixed sprite (2d text) rendering
 * fixed (very basically for now, did not migrated the old , finetuned ones yet) controls
 * fixed three.CSG
 * minor fixes all around, still plenty to fix...