git/odb: implement odb.FileStorer for on disc object cache
git/odb: implement odb.FileStorer for on disc object cache

aleb/git-lfs,Jericho25/-git-lfs_miilkyway,Jericho25/-git-lfs_miilkyway,github/git-lfs,aleb/git-lfs,github/git-lfs,Jericho25/-git-lfs_miilkyway,dakotahawkins/git-lfs,dakotahawkins/git-lfs,dakotahawkins/git-lfs,aleb/git-lfs,github/git-lfs