gettext: do not translate empty string

The gettext .po files have a header, but it looks like the
translation specification for an empty string.  This results in
_("") actually returning that header.

Check the input to _() and do not call gettext() on an empty string;
in some places, we run _(opts->help) where opts->help may be empty.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'sz/submodule-force-update' into pu

We may want a documentation update and a few tests.

Kicked back to 'pu'.

* sz/submodule-force-update:
  Make 'git submodule update --force' always check out submodules.
Merge branch 'jk/no-more-pre-exec-callback' into pu

(Originally merged to 'next' on 2012-07-23)

Will defer until the end of the 2012,
waiting for older "less" to go extinct.

* jk/no-more-pre-exec-callback:
  pager: drop "wait for output to run less" hack
Merge branch 'jc/maint-push-refs-all' into pu

Allows pushing and fetching refs/stash.
Need to send it out to the list for review.

* jc/maint-push-refs-all:
  get_fetch_map(): tighten checks on dest refs
  fetch/push: allow refs/*:refs/*
Merge branch 'ms/git-svn-1.7' into pu

A series by Michael Schwern via Eric to update git-svn to revamp the
way URLs are internally passed around, to make it work with SVN 1.7.

Will merge to 'next' after pinging Eric to double check and then to 'master'.

* ms/git-svn-1.7:
  git-svn: remove ad-hoc canonicalizations
  git-svn: canonicalize newly-minted URLs
  git-svn: introduce add_path_to_url function
  git-svn: canonicalize earlier
  git-svn: replace URL escapes with canonicalization
  git-svn: attempt to mimic SVN 1.7 URL canonicalization
  t9107: fix typo
  t9118: workaround inconsistency between SVN versions
  Git::SVN{,::Ra}: canonicalize earlier
  git-svn: path canonicalization uses SVN API
  Git::SVN::Utils: remove irrelevant comment
  git-svn: add join_paths() to safely concatenate paths
  git-svn: factor out _collapse_dotdot function
  git-svn: use SVN 1.7 to canonicalize when possible
  git-svn: move canonicalization to Git::SVN::Utils
  use Git::SVN{,::RA}->url accessor globally
  use Git::SVN->path accessor globally
  Git::SVN::Ra: use accessor for URLs
  Git::SVN: use accessor for URLs internally
  Git::SVN: use accessors internally for path
Merge branch 'jc/add-delete-default' into pu

"git add dir/" updated modified files and added new files, but does
not notice removed files, which may be "Huh?" to some users.  They
can of course use "git add -A dir/", but why should they?

Resurrected from graveyard, as I thought it was a worthwhile thing
to do in the longer term; waiting for comments.

* jc/add-delete-default:
  git add: notice removal of tracked paths by default
Merge branch 'pw/p4-use-client-spec-branch-detection' into pu

Will merge to 'next' and soon to 'master'.

* pw/p4-use-client-spec-branch-detection:
  git p4: make branch detection work with --use-client-spec
  git p4: do wildcard decoding in stripRepoPath
  git p4: set self.branchPrefixes in initialization
  git p4 test: add broken --use-client-spec --detect-branches tests
  git p4 test: move client_view() function to library
Merge branch 'pw/p4-submit-conflicts' into pu

Waiting for the dust to settle.

* pw/p4-submit-conflicts:
  git p4: add submit --prepare-p4-only option
  git p4: add submit --dry-run option
  git p4: accept -v for --verbose
  git p4: revert deleted files after submit cancel
  git p4: rearrange submit template construction
  git p4: test clean-up after failed submit, fix added files
  git p4: standardize submit cancel due to unchanged template
  git p4: move conflict prompt into run, use [c]ontinue and [q]uit
  git p4: remove submit failure options [a]pply and [w]rite
  git p4: gracefully fail if some commits could not be applied
  git p4 test: use p4d -L option to suppress log messages
  git p4 test: remove bash-ism of combined export/assignment
Merge branch 'lt/commit-tree-guess-utf-8' into pu

Teaches "git commit" and "git commit-tree" the "we are told to use
utf-8 in log message, but this does not look like utf-8---attempt to
pass it through convert-from-latin1-to-utf8 and see if it makes
sense" heuristics "git mailinfo" already uses.

A draft from Linus received privately without a log message.
Expecting a reroll.

* lt/commit-tree-guess-utf-8:
  commit/commit-tree: correct latin1 to utf-8
Merge branch 'tx/relative-in-the-future' into pu

Not my itch; rewritten an earlier submission by Tom Xue into
somewhat more maintainable form, though it breaks existing i18n.

* tx/relative-in-the-future:
  date: show relative dates in the future
  date: refactor the relative date logic from presentation
Merge branch 'jl/submodule-rm' into pu

Expecting a reroll.

* jl/submodule-rm:
  rm: remove submodules from the index and the .gitmodules file
  rm: don't fail when removing populated submodules
Merge branch 'mb/remote-default-nn-origin' into pu

When the user does not specify what remote to interact with, we
often attempt to use 'origin'.  This can now be customized via a
configuration variable.

Expecting a reroll.
"The first remote becomes the default" bit is better done as a
separate step.

* mb/remote-default-nn-origin:
  Teach get_default_remote to respect remote.default.
  Test that plain "git fetch" uses remote.default when on a detached HEAD.
  Teach clone to set remote.default.
  Teach "git remote" about remote.default.
  Teach remote.c about the remote.default configuration setting.
  Rename remote.c's default_remote_name static variables.
Merge branch 'jc/split-blob' into pu

Not ready.

I finished the streaming checkout codepath, but as explained in
127b177 (bulk-checkin: support chunked-object encoding, 2011-11-30),
these are still early steps of a long and painful journey. At least
pack-objects and fsck need to learn the new encoding for the series
to be usable locally, and then index-pack/unpack-objects needs to
learn it to be used remotely.

Given that I heard a lot of noise that people want large files, and
that I was asked by somebody at GitTogether'11 privately for an
advice on how to pay developers (not me) to help adding necessary
support, I am somewhat dissapointed that the original patch series
that was sent long time ago still remains here without much comments
and updates from the developer community. I even made the interface
to the logic that decides where to split chunks easily replaceable,
and I deliberately made the logic in the original patch extremely
stupid to entice others, especially the "bup" fanbois, to come up
with a better logic, thinking that giving people an easy target to
shoot for, they may be encouraged to help out. The plan is not
working :-<.

* jc/split-blob:
  chunked-object: streaming checkout
  chunked-object: fallback checkout codepaths
  bulk-checkin: support chunked-object encoding
  bulk-checkin: allow the same data to be multiply hashed
  new representation types in the packstream
  packfile: use varint functions

Conflicts:
	builtin/pack-objects.c
	streaming.c
	t/t1050-large.sh
Merge branch 'tg/index-v5' into pu

A GSoC project, queued here primarily to give people an easier
access to the state of the last posted version.

* tg/index-v5:
  p0002-index.sh: add perf test for the index formats
  update-index.c: rewrite index when index-version is given
  Write resolve-undo data for index-v5
  Write index-v5 cache-tree data
  Write index-v5
  Read cache-tree in index-v5
  Read resolve-undo data
  Read index-v5
  Make in-memory format aware of stat_crc
  Add documentation of the index-v5 file format
  t2104: Don't fail for index versions other than [23]
  read-cache.c: Re-read index if index file changed
  Move index v2 specific functions to their own file

Conflicts:
	read-cache.c
Merge branch 'kk/maint-for-each-ref-multi-sort' into pu

A small and sensible fix, even though the accompanying test seems to
touch too many unrelated existing ones needlessly, which may want to
be fixed by a reroll.

* kk/maint-for-each-ref-multi-sort:
  for-each-ref: Fix sort with multiple keys
  t6300: test sort with multiple keys
Merge branch 'tr/maint-parseopt-avoid-empty' into pu

A workaround to avoid doing _(""), which translates to magic string
in the .po files.

* tr/maint-parseopt-avoid-empty:
  gettext: do not translate empty string
Merge branch 'nd/i18n-parseopt-help' into pu

A lot of i18n mark-up for the help text from "git <cmd> -h".

* nd/i18n-parseopt-help: (54 commits)
  i18n: shortlog: mark parseopt strings for translation
  i18n: rm: mark parseopt strings for translation
  i18n: revert, cherry-pick: mark parseopt strings for translation
  i18n: rev-parse: mark parseopt strings for translation
  i18n: reset: mark parseopt strings for translation
  i18n: rerere: mark parseopt strings for translation
  i18n: status: mark parseopt strings for translation
  i18n: replace: mark parseopt strings for translation
  i18n: remote: mark parseopt strings for translation
  i18n: read-tree: mark parseopt strings for translation
  i18n: push: mark parseopt strings for translation
  i18n: prune: mark parseopt strings for translation
  i18n: prune-packed: mark parseopt strings for translation
  i18n: pack-refs: mark parseopt strings for translation
  i18n: pack-objects: mark parseopt strings for translation
  i18n: notes: mark parseopt strings for translation
  i18n: name-rev: mark parseopt strings for translation
  i18n: mv: mark parseopt strings for translation
  i18n: mktree: mark parseopt strings for translation
  i18n: merge: mark parseopt strings for translation
  ...

Conflicts:
	builtin/grep.c
	builtin/remote.c
	builtin/revert.c
Merge branch 'fa/remote-svn' into pu

* fa/remote-svn:
  Add a test script for remote-svn
  remote-svn: add marks-file regeneration
  Add a svnrdump-simulator replaying a dump file for testing
  remote-svn: add incremental import
  remote-svn: Activate import/export-marks for fast-import
  Create a note for every imported commit containing svn metadata
  vcs-svn: add fast_export_note to create notes
  Allow reading svn dumps from files via file:// urls
  remote-svn, vcs-svn: Enable fetching to private refs
  When debug==1, start fast-import with "--stats" instead of "--quiet"
  Add documentation for the 'bidi-import' capability of remote-helpers
  Connect fast-import to the remote-helper via pipe, adding 'bidi-import' capability
  Add argv_array_detach and argv_array_free_detached
  Add svndump_init_fd to allow reading dumps from arbitrary FDs
  Add git-remote-testsvn to Makefile
  Implement a remote helper for svn in C
Merge branch 'fa/vcs-svn' into pu

Rerolled with another round of fix-up squashed in.

* fa/vcs-svn:
  vcs-svn: remove repo_tree
  vcs-svn/svndump: rewrite handle_node(), begin|end_revision()
  vcs-svn/svndump: restructure node_ctx, rev_ctx handling
  svndump: move struct definitions to .h