[PATCH v6 00/17] Port branch.c to use ref-filter's printing options

This is part of unification of the commands 'git tag -l, git branch -l and git for-each-ref'. This ports over branch.c to use ref-filter's printing options.

Initially posted here: $(gmane/279226). It was decided that this series would follow up after refactoring ref-filter parsing mechanism, which is now merged into master (9606218b32344c5c756f7c29349d3845ef60b80c).

v1 can be found here: $(gmane/288342) v2 can be found here: $(gmane/288863) v3 can be found here: $(gmane/290299) v4 can be found here: $(gmane/291106) v5b can be found here: $(gmane/292467)

Changes in this version:

1. Rebased on top of f307218 (t6302: simplify non-gpg cases). This
patch ensures that we only use signed tags when GPG is installed and
effectively gets rid of the bug introduced by 01/17 (ref-filter:
implement %(if), %(then), and %(else) atoms)[1].

[1]: $(gmane/293901)

Karthik Nayak (17):
  ref-filter: implement %(if), %(then), and %(else) atoms
  ref-filter: include reference to 'used_atom' within 'atom_value'
  ref-filter: implement %(if:equals=<string>) and
    %(if:notequals=<string>)
  ref-filter: modify "%(objectname:short)" to take length
  ref-filter: move get_head_description() from branch.c
  ref-filter: introduce format_ref_array_item()
  ref-filter: make %(upstream:track) prints "[gone]" for invalid
    upstreams
  ref-filter: add support for %(upstream:track,nobracket)
  ref-filter: make "%(symref)" atom work with the ':short' modifier
  ref-filter: introduce refname_atom_parser_internal()
  ref-filter: introduce symref_atom_parser() and refname_atom_parser()
  ref-filter: make remote_ref_atom_parser() use
    refname_atom_parser_internal()
  ref-filter: add `:dir` and `:base` options for ref printing atoms
  ref-filter: allow porcelain to translate messages in the output
  branch, tag: use porcelain output
  branch: use ref-filter printing APIs
  branch: implement '--format' option

 Documentation/git-branch.txt       |   7 +-
 Documentation/git-for-each-ref.txt |  87 +++++--
 builtin/branch.c                   | 277 +++++++---------------
 builtin/tag.c                      |   2 +
 ref-filter.c                       | 456 +++++++++++++++++++++++++++++++------
 ref-filter.h                       |   7 +
 t/t3203-branch-output.sh           |  16 +-
 t/t6040-tracking-info.sh           |   2 +-
 t/t6300-for-each-ref.sh            |  73 +++++-
 t/t6302-for-each-ref-filter.sh     |  94 ++++++++
 10 files changed, 726 insertions(+), 295 deletions(-)