Merge branch 'maint-2.5' into maint-2.6

* maint-2.5: Git 2.5.5 Git 2.4.11 list-objects: pass full pathname to callbacks list-objects: drop name_path entirely list-objects: convert name_path to a strbuf show_object_with_name: simplify by using path_name() http-push: stop using name_path tree-diff: catch integer overflow in combine_diff_path allocation add helpers for detecting size_t overflow