[PATCH] gitk: Add a visual tag for remote refs

[PATCH] gitk: Add a visual tag for remote refs

This patch partly changes the background color for remote refs.
It makes it easy to quickly distinguish remote refs from local
developer branches.

I ignore remote HEADs, as these really should be drawn as
aliases to other heads. But there is no simple way to
detect that HEADs really are aliases for other refs via
"git-ls-remote".

Signed-off-by: Josef Weidendorfer <Josef.Weidendorfer@gmx.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>