[RFC] External diff viewer

I have just pushed a patch to let qgit support external diff viewers.
Git repo is

http://digilander.libero.it/mcostalba/scm/qgit.git

This is how it works:

From menu View->'External diff' it is possible to invoke an external

diff viewer, as example to view the diffs in a two vertical tiled
windows.

External diff viewer shows the diffs between two files.
First file is the current selected file of current revision. Second
file is the same file of the parent revision or of a specific revision
if "diff to selected sha" feature is enabled (CTRL + RIGHT CLICK on
chosen revision with *internal* diff viewer window open).

Default external viewer is kompare, but it is possible to set a
preferred one from Edit->Settings->External Diff Viewer.


I don't think the feature is  already release ready, so I just pushed
the patch in git repo for interested people.

Feedback/comments /bugs or something to change or improve before to release?

Thanks
Marco