Merge branch 'jn/thinner-wrapper'

* jn/thinner-wrapper:
Remove pack file handling dependency from wrapper.o
pack-objects: mark file-local variable static
wrapper: give zlib wrappers their own translation unit
strbuf: move strbuf_branchname to sha1_name.c
path helpers: move git_mkstemp* to wrapper.c
wrapper: move odb_* to environment.c
wrapper: move xmmap() to sha1_file.c

diff --cc Makefile
Simple merge

diff --cc builtin/pack-objects.c
Simple merge

diff --cc environment.c
Simple merge

diff --cc git-compat-util.h
Simple merge

diff --cc sha1_file.c
Simple merge

diff --cc sha1_name.c
Simple merge