Bug 450320 - Compare viewer should show Green/Red for addition/removal

This enables usage of different color to highlight
addition/removal/edition in case of a 2 way change with only "outgoing"
changes.
This is the typical case when looking at history or comparing with a
commit.

Change-Id: I6aa09c7f421a6481c9990904963f6e24009edc9b
Signed-off-by: Mickael Istria <mistria@redhat.com>
4 files changed