Some new CODEF Tutorials uploaded

Hi everyone!

At the request of a couple of fans, I have started work again on some new CODEF old school demo tutorials!

The following sections have been added:

- How to make a Gradient background
- How to move an object either in a "bounce" effect, or a "swing" effect using Math.cos and Math.sin.
- Raster effects
- Four different types of starfield 
- Three different versions of music playback.
- Horizontal and Vertical scrolltexts as well!

And finally, several effects combined to make a finished demoscreen! :-)

They can be found here. Enjoy!