Another bloody update of L3DT 2.3b

There was a fault in the way some older parts of L3DT handled file paths. I noticed this when trying to use the 'register new climate…' feature, which simply didn't work at all. This has been fixed in both Standard and Professional editions, which are available on their respective downloads pages.

Both editions are now at version 2.3b rev 22 (15-Dec-05).