Update split function...

[sdlime]

From steve:

- Fixing behavior of split function (soon to be msStringSplit). At present it
ignores consecutive delimeters. This presents a problem with CSV joined tables
where ,, actually means a field is empty. I'd like to change the behavior to
return an empty string.

From dan:

- While you're at it, I would like to that you also add an option to 
honour strings.  Actually, there is a function called 
CSLTokenizeString2() gdal/port/cpl_string.c that does that and more and 
that you could simply copy after a few small changes.

[sdlime]

Still a friggin' problem. Giving this one a milestone so it actually gets attention.

Steve