Site redesign and new version

I have completely redesigned the env3d website. Besides looking way better, I have also included complete lessons on how to use env3d in CS1. You can find them under the "Learn" section of the website.

A new version of env3d is also available. A couple of major changes:

* No need to "install" the extension anymore. Simply download and open the blank project, and follow the lessons to add your own code.

* You can now create 3D-accelerated applets for online distribution.

If you like env3d or have questions or comments, feel free to drop me a line.