* Generate Diff and Patch direct from Pull head
Fix#10932
Also fix "Empty Diff/Patch File when pull is merged"
Closes#10934
Signed-off-by: Andrew Thornton <art27@cantab.net>
* Add tests to ensure that diff does not change
Signed-off-by: Andrew Thornton <art27@cantab.net>
* Ensure diffs and pulls pages work if head branch is deleted too
Signed-off-by: Andrew Thornton <art27@cantab.net>