small bugfix in selection helper to avoid double outlines
- lots of visualEditor improvements and bug fixes:
 * fixes #133 : axis overlay works correctly again
 * fixes #132 : outlines can now be enabled/disabled
 * fixes #131 : view offset in firefox
 * fixes #130 : view and webgl related elements are now initialized correctly, no more black screen on startup
 * lots of cleanup and improvements
 * warning : changed how 3d view is updated/rendered : this might be temporary only, but it is now using requestAnimationFrame for rendering at a constant framerate, regardless
of user input