Updated web site

I have done an update of the web page.

The biggest change is that I have put the documentation online and the 
download link goes directly to the SourceForge download page. You will 
note that the tutorial is very incomplete as it only covers gtksheet. 
Any contributions to better documentation would be most welcome.

If there are any issues or comments, please let me know.

Regards,
Roy Rankin

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