Reducing tab size

[Sean Egan]

An update on my tab-width-reduction experiment:

Tab labels are truncated at a space or @. This needs two updates: only
truncate at spaces for aliases, as for someone with the AIM screenname
"I am an AIM screenname," "I" does not make a useful label.
Additionally, it should detect if it's creating duplicate tabs, and
not truncate in that case. For instance, I'd rather see "Mark Spencer"
and "Mark Doliner" than two "Mark"s

Close buttons have been replaced. They used to be a 16x16 pixel icon
inside a GtkButton, which added a bunch of additional padding and
borders (for small amounts of a 'bunch'). I replaced this to use just
a GtkLabel with its text set to 'U+2715 MULTIPLICATION X' The result
looks great regardless of theme or font sizes. Is super-sleek, and (in
my opinion, at least) much better than what we had before.

And, most controversially, status icons are currently replaced with
text formatting: normal formatting for available, strike-through for
offline, and italics for unavailable. I additionally want to add a
tooltip on the text to explain what the formatting means.

A screenshot: http://pidgin.im/~seanegan/tabs.png

-s.