Patch Set 3: No score; No score

The handling of files that are both staged and dirty has issues:

- The entry in "Modified" has no decorator in this case.
- double clicking on the entry in "Staged" opens a compare view which compares the content of the working tree file with the HEAD, I would expect a comparison of the staged content with the head, however, there is no action for this yet.
- "Compare With -> ..." does not the right thing on a staged entry (if it is also dirty), it should compare the staged content with the head

An alphabetic ordering of the repositories would be nice.

I think that it is not a problem that unstaging is not yet possible. The view is useful nevertheless.