avoid segfault on submodule.*.path set to an empty "true"

Git fails due to a segmentation fault if a submodule path is empty.
Here is an example .gitmodules that will cause a segmentation fault:

    [submodule "foo-module"]
      path
      url = http://host/repo.git
    $ git status
    Segmentation fault (core dumped)

This is because the parsing of "submodule.*.path" is not prepared to
see a value-less "true" and assumes that the value is always
non-NULL (parsing of "ignore" has the same problem).

Fix it by checking the NULL-ness of value and complain with
config_error_nonbool().

Signed-off-by: Jharrod LaFon <jlafon@eyesopen.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'jl/some-submodule-config-are-not-boolean' into jch

* jl/some-submodule-config-are-not-boolean:
  avoid segfault on submodule.*.path set to an empty "true"
### 2.0
Merge branch 'jc/push-2.0-default-to-simple' into jch

* jc/push-2.0-default-to-simple:
  push: switch default from "matching" to "simple"

# Conflicts:
# 	Documentation/config.txt
# 	Documentation/git-push.txt
# 	builtin/push.c
Merge branch 'jn/add-2.0-u-A-sans-pathspec' into jch

* jn/add-2.0-u-A-sans-pathspec:
  git add: -u/-A now affects the entire working tree

# Conflicts:
# 	builtin/add.c
Merge branch 'jc/add-2.0-ignore-removal' into jch

Updated endgame for "git add <pathspec>" that defaults to "--all"
aka "--no-ignore-removal".

* jc/add-2.0-ignore-removal:
  git add <pathspec>... defaults to "-A"

# Conflicts:
# 	builtin/add.c
Merge branch 'jc/core-checkstat-2.0' into jch

* jc/core-checkstat-2.0:
  core.statinfo: remove as promised in Git 2.0
Merge branch 'jc/hold-diff-remove-q-synonym-for-no-deletion' into jch

* jc/hold-diff-remove-q-synonym-for-no-deletion:
  diff: remove "diff-files -q" in a version of Git in a distant future

# Conflicts:
# 	diff.c
Merge branch 'jc/reflog-doc' into pu

Document rules to use GIT_REFLOG_ACTION variable in the scripted
Porcelain.  git-rebase--interactive locally violates this, but it
is a leaf user that does not call out to or dot-sources other
scripts, so fixing it is not all that urgent.

* jc/reflog-doc:
  setup_reflog_action: document the rules for using GIT_REFLOG_ACTION

# Conflicts:
# 	Documentation/git.txt
Merge branch 'tf/gitweb-ss-tweak' into pu

Comments?

* tf/gitweb-ss-tweak:
  gitweb: make search help link less ugly
  gitweb: omit the repository owner when it is unset
  gitweb: vertically centre contents of page footer
  gitweb: ensure OPML text fits inside its box
Merge branch 'mg/more-textconv' into pu

Make "git grep" and "git show" pay attention to --textconv when
dealing with blob objects.

I thought this was pretty well designed and executed, but it seems
there are some doubts on the list; kicked back to 'pu'.

* mg/more-textconv:
  grep: honor --textconv for the case rev:path
  grep: allow to use textconv filters
  t7008: demonstrate behavior of grep with textconv
  cat-file: do not die on --textconv without textconv filters
  show: honor --textconv for blobs
  diff_opt: track whether flags have been set explicitly
  t4030: demonstrate behavior of show with textconv

# Conflicts:
# 	diff.h
# 	object.c
# 	object.h
# 	t/t8007-cat-file-textconv.sh
Merge branch 'jh/shorten-refname' into pu

When remotes/origin/HEAD is not a symbolic ref, "rev-parse
--abbrev-ref remotes/origin/HEAD" ought to show "origin", not
"origin/HEAD", which is fixed with this series (if it is a symbolic
ref that points at remotes/origin/something, then it should show
"origin/something" and it already does).

$gmane/225137

* jh/shorten-refname:
  t1514: refname shortening is done after dereferencing symbolic refs
  shorten_unambiguous_ref(): Fix shortening refs/remotes/origin/HEAD to origin
  t1514: Demonstrate failure to correctly shorten "refs/remotes/origin/HEAD"
  t1514: Add tests of shortening refnames in strict/loose mode

# Conflicts:
# 	refs.c
Merge branch 'jk/gitweb-utf8' into pu

Various fixes to gitweb.

Drew Northup volunteered to take a look into this.
$gmane/226216

* jk/gitweb-utf8:
  gitweb: Fix broken blob action parameters on blob/commitdiff pages
  gitweb: Don't append ';js=(0|1)' to external links
  gitweb: Make feed title valid utf8
  gitweb: Fix utf8 encoding for blob_plain, blobdiff_plain, commitdiff_plain, and patch
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.

tying its loose ends.

* jc/format-patch:
  format-patch: --inline-single
  format-patch: rename "no_inline" field

# Conflicts:
# 	builtin/log.c
# 	log-tree.c
# 	pretty.c
Merge branch 'jc/show-branch' into pu

* jc/show-branch:
  show-branch: use commit slab to represent bitflags of arbitrary width
  show-branch.c: remove "all_mask"
  show-branch.c: abstract out "flags" operation
  show-branch.c: lift all_mask/all_revs to a global static
  show-branch.c: update comment style

# Conflicts:
# 	builtin/show-branch.c
Merge branch 'rj/read-default-config-in-show-ref-pack-refs' into pu

The changes themselves are probably good, but it is unclear what
basic setting needs to be read for which exact operation.

$gmane/228294

* rj/read-default-config-in-show-ref-pack-refs:
  ### DONTMERGE: needs better explanation on what config they need
  pack-refs.c: Add missing call to git_config()
  show-ref.c: Add missing call to git_config()
Merge branch 'tr/merge-recursive-index-only' into pu

Will hold, until we get any user.

* tr/merge-recursive-index-only:
  merge-recursive: -Xindex-only to leave worktree unchanged
  merge-recursive: untangle double meaning of o->call_depth
  merge-recursive: remove dead conditional in update_stages()