merge/pull Check for untrusted good GPG signatures

When --verify-signatures is specified, abort the merge in case a good
GPG signature from an untrusted key is encountered.

Signed-off-by: Sebastian Götte <jaseg@physik-pool.tu-berlin.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
pretty printing: extend %G? to include 'N' and 'U'

Expand %G? in pretty format strings to 'N' in case of no GPG signature
and 'U' in case of a good but untrusted GPG signature in addition to
the previous 'G'ood and 'B'ad. This eases writing anyting parsing
git-log output.

Signed-off-by: Sebastian Götte <jaseg@physik-pool.tu-berlin.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'sg/gpg-sig' into pu

Teach "merge/pull" to optionally verify and reject commits that are
not signed properly.

* sg/gpg-sig:
  pretty printing: extend %G? to include 'N' and 'U'
  merge/pull Check for untrusted good GPG signatures
  merge/pull: verify GPG signatures of commits being merged
  commit.c/GPG signature verification: Also look at the first GPG status line
  Move commit GPG signature verification to commit.c
Merge branch 'jc/format-patch' into pu

A new option to send a single patch to the standard output to be
appended at the bottom of a message.  I personally have no need for
this, but it was easy enough to cobble together.  Tests, docs and
stripping out more MIMEy stuff are left as exercises to interested
parties.

* jc/format-patch:
  format-patch: --inline-single
  format-patch: rename "no_inline" field
Merge branch 'nd/magic-pathspecs' into pu

Migrate the rest of codebase to use "struct pathspec" more.

* nd/magic-pathspecs: (45 commits)
  Rename field "raw" to "_raw" in struct pathspec
  pathspec: support :(glob) syntax
  pathspec: make --literal-pathspecs disable pathspec magic
  pathspec: support :(literal) syntax for noglob pathspec
  Kill limit_pathspec_to_literal() as it's only used by parse_pathspec()
  parse_pathspec: preserve prefix length via PATHSPEC_PREFIX_ORIGIN
  parse_pathspec: make sure the prefix part is wildcard-free
  tree-diff: remove the use of pathspec's raw[] in follow-rename codepath
  Remove match_pathspec() in favor of match_pathspec_depth()
  Remove init_pathspec() in favor of parse_pathspec()
  Remove diff_tree_{setup,release}_paths
  Convert common_prefix() to use struct pathspec
  Convert add_files_to_cache to take struct pathspec
  Convert {read,fill}_directory to take struct pathspec
  Convert refresh_index to take struct pathspec
  Convert report_path_error to take struct pathspec
  checkout: convert read_tree_some to take struct pathspec
  Convert unmerge_cache to take struct pathspec
  Convert run_add_interactive to use struct pathspec
  Convert read_cache_preload() to take struct pathspec
  ...
Merge branch 'jk/merge-tree-added-identically' into pu

We would most likely want to change things the other way around.

* jk/merge-tree-added-identically:
  merge-tree: fix "same file added in subdir"
Merge branch 'rr/triangle' into pu

Support "pull from one place, push to another place" workflow
better by introducing remote.pushdefault (overrides the "origin"
thing) and branch.*.pushremote (overrides the branch.*.remote).

* rr/triangle:
  remote.c: introduce branch.<name>.pushremote
  remote.c: introduce remote.pushdefault
  remote.c: introduce a way to have different remotes for fetch/push
  t5516 (fetch-push): drop implicit arguments from helper functions
  t5516 (fetch-push): update test description
  remote.c: simplify a bit of code using git_config_string()

# Conflicts:
# 	t/t5516-fetch-push.sh