patch to skip between conflicts

[Tom Hughes <tom hughes palm com>]

 I've been doing a lot of git merging lately. With files that have a 
lot of non-conflicting merges it can require a lot of clicking and 
scrolling to get to the conflicts, so I went ahead and added "next 
conflict" and "prev conflict" buttons that skip directly to the 
conflicts. The code could be more efficient, but it's a fairly simple 
change and seems to work. (It also seems to work with svn, but I haven't 
used it much for that.)

Looking at the meld bugs, it looks like I wasn't the only one interested 
in this: https://bugzilla.gnome.org/show_bug.cgi?id=602873 . I attached 
the patch to that.

Tom