Merge branch 'jc/maint-1.6.0-keep-pack'

* jc/maint-1.6.0-keep-pack: pack-objects: don't loosen objects available in alternate or kept packs t7700: demonstrate repack flaw which may loosen objects unnecessarily Remove --kept-pack-only option and associated infrastructure pack-objects: only repack or loosen objects residing in "local" packs git-repack.sh: don't use --kept-pack-only option to pack-objects t7700-repack: add two new tests demonstrating repacking flaws Conflicts: t/t7700-repack.sh