cleaned and released kal-shlib-* code and dd_rhelp

This is a long time since I wrote the first line of this shell script library which has followed me since then.

These library were managed on subversion, so this was the opportunity to move them toward GIT.

Same for dd_rhelp which received a small but constant flow of thanks, remarks, and patches from all over the world. And I wasn't always very reactive.

Hope this will help people mess around with the code as they wish.