git-gui: support for diff3 conflict style

This adds highlight support for the diff3 conflict style.

The common pre-image will be reversed to --, because it has been removed
and replaced with ours or theirs side respectively.

Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Pratyush Yadav <me@yadavpratyush.com>
2 files changed