[Kst] ASCII config patch

[Barth Netterfield]

Regarding ascii configuration:

It seems to me that perhaps the correct way to do this is to make a separate 
csv data source, rather than using the generic ascii one.  csv seems to be 
pretty well documented  - see

http://www.creativyst.com/Doc/Articles/CSV/CSV01.htm

and, as it is used by exel, very common.  So it would be really great to 
support it.  

Supporting csv via a highly configureable generic data source, however, seems 
like the *wrong* way to do it.  I would prefer a virtually non-configurable 
data source which supports it directly.

The one configuration option we *might* need is whether the first row contains 
field names.  We could guess correctly with pretty high reliability, by 
seeing if the first row is numbers or not, but we should allow a checkbox 
override to our guess.

I guess we could provide pretty reliable heurisics to decide if the file is 
csv or generic ascii (eg, is it comma separated... does it end in .csv) but 
we might want to provide a way of overriding the choice in the datasource 
selection widget.

In the first instance, we should try for the pure automagic approach.

Thoughts?
cbn