This mostly moves existing code from builtin/tag.c (for signing)
and builtin/verify-tag.c (for verifying) to a new gpg-interface.c
file to provide a more generic library interface.

 - sign_buffer() takes a payload strbuf, a signature strbuf, and a signing
   key, runs "gpg" to produce a detached signature for the payload, and
   appends it to the signature strbuf. The contents of a signed tag that
   concatenates the payload and the detached signature can be produced by
   giving the same strbuf as payload and signature strbuf.

 - verify_signed_buffer() takes a payload and a detached signature as
   <ptr, len> pairs, and runs "gpg --verify" to see if the payload matches
   the signature. It can optionally capture the output from GPG to allow
   the callers to pretty-print it in a way more suitable for their
   contexts.

"verify-tag" (aka "tag -v") used to save the whole tag contents as if it
is a detached signature, and fed gpg the payload part of the tag. It
relied on gpg to fail when the given tag is not signed but just is
annotated.  The updated run_gpg_verify() function detects the lack of
detached signature in the input, and errors out without bothering "gpg".

Signed-off-by: Junio C Hamano <gitster@pobox.com>

* jn/no-g-plus-s-on-bsd:
  Makefile: do not set setgid bit on directories on GNU/kFreeBSD

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Ever since mergetool--lib was split into multiple files in
v1.7.7-rc0~3^2~1 (2011-08-18), the Makefile takes care to reset umask
and use tar --no-owner when installing merge tool definitions to
$(gitexecdir)/mergetools/.  Unfortunately it does not take into
account the possibility that the permission bits of the files being
copied might already be wrong.

Rather than fixing the "tar" incantation and making it even more
complicated, let's just use the "install" utility.  This only means
losing the ability to install executables and subdirectories of
mergetools/, which wasn't used.

Noticed by installing from a copy of git checked out with umask 002.
Compare v1.6.0.3~81^2 (Fix permission bits on sources checked out with
an overtight umask, 2008-08-21).

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

* jk/argv-array:
  run_hook: use argv_array API
  checkout: use argv_array API
  bisect: use argv_array API
  quote: provide sq_dequote_to_argv_array
  refactor argv_array into generic code
  quote.h: fix bogus comment
  add sha1_array API docs

* rj/quietly-create-dep-dir:
  Makefile: Make dependency directory creation less noisy

* jc/receive-verify:
  receive-pack: check connectivity before concluding "git push"
  check_everything_connected(): libify
  check_everything_connected(): refactor to use an iterator
  fetch: verify we have everything we need before updating our ref

Conflicts:
	builtin/fetch.c

* rr/revert-cherry-pick-continue:
  builtin/revert.c: make commit_list_append() static
  revert: Propagate errors upwards from do_pick_commit
  revert: Introduce --continue to continue the operation
  revert: Don't implicitly stomp pending sequencer operation
  revert: Remove sequencer state when no commits are pending
  reset: Make reset remove the sequencer state
  revert: Introduce --reset to remove sequencer state
  revert: Make pick_commits functionally act on a commit list
  revert: Save command-line options for continuing operation
  revert: Save data for continuing after conflict resolution
  revert: Don't create invalid replay_opts in parse_args
  revert: Separate cmdline parsing from functional code
  revert: Introduce struct to keep command-line options
  revert: Eliminate global "commit" variable
  revert: Rename no_replay to record_origin
  revert: Don't check lone argument in get_encoding
  revert: Simplify and inline add_message_to_msg
  config: Introduce functions to write non-standard file
  advice: Introduce error_resolve_conflict

* da/make-auto-header-dependencies:
  Makefile: Improve compiler header dependency check

* fk/make-auto-header-dependencies:
  Makefile: Use computed header dependencies if the compiler supports it