Merge branch 'jn/maint-setup-fix' (early part) into jn/paginate-fix

* 'jn/maint-setup-fix' (early part): Revert "rehabilitate 'git index-pack' inside the object store" setup: do not forget working dir from subdir of gitdir t4111 (apply): refresh index before applying patches to it setup: split off get_device_or_die helper setup: split off a function to handle hitting ceiling in repo search setup: split off code to handle stumbling upon a repository setup: split off a function to checks working dir for .git file setup: split off $GIT_DIR-set case from setup_git_directory_gently tests: try git apply from subdir of toplevel t1501 (rev-parse): clarify