Merge branch 'maint'

* maint:
  Makefile: fix shell quoting
  tests: propagate $(TAR) down from the toplevel Makefile
  index-pack.c: correctly initialize appended objects
  send-email: find body-encoding correctly

diff --cc Makefile
Simple merge

diff --cc git-send-email.perl
Simple merge

diff --cc index-pack.c
Simple merge

diff --cc t/t5000-tar-tree.sh
Simple merge