glossary: extend "detached HEAD" description

When we introduced the concept of "detached HEAD", we made sure that
commands that operate on the history of the current branch "just
work" in that state.  They update the HEAD to point at the new
history without affecting any branch when the HEAD is detached, just
like they update the tip of the "current branch" to point at the new
history when HEAD points at a specific branch.

As this is done as the natural extension for these commands, we did
not, we still do not, and we do not want to repeat "A detached HEAD
is updated without affecting any branch" when describing what each
and every one of these commands that operates "on the current branch"
does.

Add a blanket description to the glossary to cover them instead.
The general principle is that operations to update the branch work
on and affect the HEAD, while operations to update the information
about a branch do not.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-merge(1): document diff-algorithm option to merge-recursive

Commit 07924d4 (diff: Introduce --diff-algorithm command line option
2013-01-16) added diff-algorithm as a parameter to the recursive merge
strategy but did not document it.  Do so.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff: allow unstuck arguments with --diff-algorithm

The argument to --diff-algorithm is mandatory, so there is no reason to
require the argument to be stuck to the option with '='.  Change this
for consistency with other Git commands.

Note that this does not change the handling of diff-algorithm in
merge-recursive.c since the primary interface to that is via the -X
option to 'git merge' where the unstuck form does not make sense.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
submodule: print graph output next to submodule log

When running "git log -p --submodule=log", the submodule log is not
indented by the graph output, although all other lines are.  Fix this by
prepending the current line prefix to each line of the submodule log.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'ap/combine-diff-coalesce-lost' into jch

Attempts to minimize "diff -c/--cc" output by coalescing the same
lines removed from the parents better, but with an O(n^2)
complexity.

* ap/combine-diff-coalesce-lost:
  combine-diff: coalesce lost lines optimally
Merge branch 'tr/packed-object-info-wo-recursion' into jch

Attempts to reduce the stack footprint of sha1_object_info()
and unpack_entry() codepaths.

* tr/packed-object-info-wo-recursion:
  sha1_file: remove recursion in unpack_entry
  Refactor parts of in_delta_base_cache/cache_or_unpack_entry
  sha1_file: remove recursion in packed_object_info
Merge branch 'tr/line-log' into jch

fixed eventually in-tree.

* tr/line-log:
  log -L: fix overlapping input ranges
  log -L: check range set invariants when we look it up
  Speed up log -L... -M
  log -L: :pattern:file syntax to find by funcname
  Implement line-history search (git log -L)
  Export rewrite_parents() for 'log -L'
  Refactor parse_loc

# Conflicts:
# 	log-tree.c
Merge branch 'kb/status-ignored-optim' into jch

"git status --ignored" had many corner case bugs.  Also the command
has been optimized by taking advantage of the fact that paths that
are already known to the index do not have to be checked against
the .gitignore mechanism most of the time.

This codepath is used not only by status but also in add and clean,
so a bug in it can result in lost data.  Extra sets of eyeballs are
very much appreciated.

* kb/status-ignored-optim:
  dir.c: git-status: avoid is_excluded checks for tracked files
  dir.c: replace is_path_excluded with now equivalent is_excluded API
  dir.c: unify is_excluded and is_path_excluded APIs
  dir.c: move prep_exclude and factor out parts of last_exclude_matching
  dir.c: git-status --ignored: don't list empty directories as ignored
  dir.c: git-status --ignored: don't list empty ignored directories
  dir.c: git-status --ignored: don't list files in ignored directories
  dir.c: git-status --ignored: don't drop ignored directories
Merge branch 'jk/filter-branch-come-back-to-original' into jch

* jk/filter-branch-come-back-to-original:
  filter-branch: return to original dir after filtering
Merge branch 'mm/status-during-revert' into jch

* mm/status-during-revert:
  status: show commit sha1 in "You are currently reverting" message
  status: show 'revert' state and status hint
Merge branch 'jk/set-upstream-error-cases' into jch

* jk/set-upstream-error-cases:
  branch: give advice when tracking start-point is missing
  branch: mention start_name in set-upstream error messages
  branch: improve error message for missing --set-upstream-to ref
  branch: factor out "upstream is not a branch" error messages
  t3200: test --set-upstream-to with bogus refs
Merge branch 'po/help-guides' into jch

"git help" learned "-g" option to show the list of guides just like
list of commands are given with "-a".

* po/help-guides:
  doc: include --guide option description for "git help"
  help: mention -a and -g option, and 'git help <concept>' usage.
  builtin/help.c: add list_common_guides_help() function
  builtin/help.c: add --guide option
  builtin/help.c: split "-a" processing into two
Merge branch 'jk/diffcore-break-divzero' into jch

* jk/diffcore-break-divzero:
  diffcore-break: don't divide by zero
Merge branch 'rr/triangle' into jch

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
Merge branch 'fc/remote-helpers-test-updates' into jch

* fc/remote-helpers-test-updates:
  remote-hg: fix hg-git test-case
  remote-bzr: remove stale check code for tests
  remote-helpers: fix the run of all tests
  remote-bzr: avoid echo -n
Merge branch 'jk/bisect-prn-unsigned' into jch

* jk/bisect-prn-unsigned:
  bisect: avoid signed integer overflow
Merge branch 'mg/texinfo-5' into jch

Strip @anchor elements in the texinfo output of the documentation,
as a single document created by concatenating our entire manual set
will produce many duplicates that makes newer texinfo unhappy.

* mg/texinfo-5:
  Documentation: Strip texinfo anchors to avoid duplicates
Merge branch 'cn/commit-amend-doc' into jch

* cn/commit-amend-doc:
  Documentation/git-commit: reword the --amend explanation
Merge branch 'jc/push-2.0-default-to-simple' (early part) into jch

* 'jc/push-2.0-default-to-simple' (early part):
  t5570: do not assume the "matching" push is the default
  t5551: do not assume the "matching" push is the default
  t5550: do not assume the "matching" push is the default
  t9401: do not assume the "matching" push is the default
  t9400: do not assume the "matching" push is the default
  t7406: do not assume the "matching" push is the default
  t5531: do not assume the "matching" push is the default
  t5519: do not assume the "matching" push is the default
  t5517: do not assume the "matching" push is the default
  t5516: do not assume the "matching" push is the default
  t5505: do not assume the "matching" push is the default
  t5404: do not assume the "matching" push is the default

Conflicts:
	t/t5516-fetch-push.sh
Merge branch 'jc/add-2.0-delete-default' (early part) into jch

* 'jc/add-2.0-delete-default' (early part):
  git add: start preparing for "git add <pathspec>..." to default to "-A"
  builtin/add.c: simplify boolean variables