Host current help on slicot.org

[KybernetikJo]

It would be nice if the current help (SLICOT v5.9) would be shown on slicot.org.

https://www.slicot.org/objects/software/shared/libindex.html

For instance, ab13hd is part of the

https://github.com/SLICOT/SLICOT-Reference/blob/main/doc/AB13HD.html

current documentation, but not shown on slicot.org.

A reference to the SLICOT version in libindex.html would be an additional improvement.