[Dev] experimentally usable sections turned on

[Alec Flett]

I've just finished a first pass at a "sections" implementation in the 
table summary view - this one is based on implementation proposal #2 
that I outlined here:

http://lists.osafoundation.org/pipermail/dev/2006-January/004962.html

obviously this first-cut is quite ugly, but its a proof-of-concept. 
There are some pretty obvious flaws, including the fact that the 
"section" UI is defined by a bunch of columns that each say [Section: 
foo] where foo is the name of the section, and the fact that you can't 
turn it off. I hope to fix some of these problems tomorrow - especially 
the ability to turn it off :)

Sections are defined by whatever you are currently sorting on - so to 
see sections in action, click on the "Triage" column header. At the 
moment sorting very basic, so that the triage statuses "now", "later" 
and "done" are sorted alphabetically, rather than by actual 
triage-order. Further, sorting by date is currently broken.

Anyway, look at it, play with it, see what you think. If this is the 
implementation we want to go with, then we can expand it further, 
otherwise we can start investigating implementation #1.

Alec