Refactoring of the internal global data structure continues.
* sb/packfiles-in-repository:
packfile: keep prepare_packed_git() private
packfile: allow find_pack_entry to handle arbitrary repositories
packfile: add repository argument to find_pack_entry
packfile: allow reprepare_packed_git to handle arbitrary repositories
packfile: allow prepare_packed_git to handle arbitrary repositories
packfile: allow prepare_packed_git_one to handle arbitrary repositories
packfile: add repository argument to reprepare_packed_git
packfile: add repository argument to prepare_packed_git
packfile: add repository argument to prepare_packed_git_one
packfile: allow install_packed_git to handle arbitrary repositories
packfile: allow rearrange_packed_git to handle arbitrary repositories
packfile: allow prepare_packed_git_mru to handle arbitrary repositories