Account for indentation of the checkin comments by git-rev-list
Account for indentation of the checkin comments by git-rev-list

This involves adding indentation when we read a commit with
git-cat-file and trimming the whitespace from the headline.

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git