[ltk-user] LTK improvements

I have a fairly large bunch of changes to ltk, mostly having to do with the text widget, but also with support for new widgets from the BWidget toolkit (such as tree).

I am not completely happy with these changes, as I am sure they require further work and/or review. They can likely be implemented much better. But since I haven't found the time to do so over the last 2 months, I thought I'd rather push them out, to prevent wasting of time in case somebody is doing the same thing in parallel.

Should I send the diffs to the list, or directly to Peter? Please note, they definitely do require reviewing.

--J.