Fix --revision-range=SINGLE_COMMIT on git.
Review Request #3926 — Created March 2, 2013 and discarded — Latest diff uploaded
Fix --revision-range=SINGLE_COMMIT on git. Before this, we would generate a diff with git diff SINGLE_COMMIT..CURRENT_HEAD but this is not what was intended and what we write in the docs. Now, we use git show SINGLE_COMMIT to really only generate the diff of the given commit.
Things like `rbtools/postreview.py -n --revision-range=master^` work as expected now.