git/odb: use lfs.TempFile in *ObjectDatabase
git/odb: use lfs.TempFile in *ObjectDatabase

github/git-lfs,dakotahawkins/git-lfs,dakotahawkins/git-lfs,aleb/git-lfs,aleb/git-lfs,github/git-lfs,aleb/git-lfs,dakotahawkins/git-lfs,github/git-lfs