Merge branch 'bw/config-h'

Fix configuration codepath to pay proper attention to commondir
that is used in multi-worktree situation, and isolate config API
into its own header file.

* bw/config-h:
config: don't implicitly use gitdir or commondir
config: respect commondir
setup: teach discover_git_directory to respect the commondir
config: don't include config.h by default
config: remove git_config_iter
config: create config.h

diff --cc apply.c
Simple merge

diff --cc archive-tar.c
Simple merge

diff --cc archive-zip.c
Simple merge

diff --cc archive.c
Simple merge

diff --cc attr.c
Simple merge

diff --cc bisect.c
Simple merge

diff --cc branch.c
Simple merge

diff --cc builtin/add.c
Simple merge

diff --cc builtin/am.c
Simple merge

diff --cc builtin/blame.c
index 749ad7f05b657ba34534a4ae6601dd5d85649b36,1a7371808ad4615052e92b792149ad7f84845776..bda1a787265e6d44d2ec0bec1e4dee5bf8de9c3b
--- 1/builtin/blame.c
--- 2/builtin/blame.c
+++ b/builtin/blame.c
@@@ -6,13 -6,22 +6,14 @@@
   */
  
  #include "cache.h"
 -#include "refs.h"
+ #include "config.h"
  #include "builtin.h"
 -#include "blob.h"
  #include "commit.h"
 -#include "tag.h"
 -#include "tree-walk.h"
  #include "diff.h"
 -#include "diffcore.h"
  #include "revision.h"
  #include "quote.h"
 -#include "xdiff-interface.h"
 -#include "cache-tree.h"
  #include "string-list.h"
  #include "mailmap.h"
 -#include "mergesort.h"
  #include "parse-options.h"
  #include "prio-queue.h"
  #include "utf8.h"

diff --cc builtin/branch.c
Simple merge

diff --cc builtin/cat-file.c
index 4bffd7a2d8eee2ea251afef70f63f646f184a339,12451205cf8929c25c57f6a2d7f7a1a0a5f11fa4..7efbc4019ac59a16ae4f147889e6f489dac1e661
--- 1/builtin/cat-file.c
--- 2/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@@ -4,8 -4,8 +4,9 @@@
   * Copyright (C) Linus Torvalds, 2005
   */
  #include "cache.h"
+ #include "config.h"
  #include "builtin.h"
 +#include "diff.h"
  #include "parse-options.h"
  #include "userdiff.h"
  #include "streaming.h"

diff --cc builtin/check-ignore.c
Simple merge

diff --cc builtin/checkout.c
Simple merge

diff --cc builtin/clean.c
Simple merge

diff --cc builtin/clone.c
Simple merge

diff --cc builtin/commit-tree.c
Simple merge

diff --cc builtin/commit.c
Simple merge

diff --cc builtin/config.c
Simple merge

diff --cc builtin/describe.c
Simple merge

diff --cc builtin/diff-files.c
Simple merge

diff --cc builtin/diff-index.c
Simple merge

diff --cc builtin/diff-tree.c
Simple merge

diff --cc builtin/diff.c
Simple merge

diff --cc builtin/difftool.c
Simple merge

diff --cc builtin/fast-export.c
Simple merge

diff --cc builtin/fetch.c
Simple merge

diff --cc builtin/fmt-merge-msg.c
Simple merge

diff --cc builtin/fsck.c
Simple merge

diff --cc builtin/gc.c
Simple merge

diff --cc builtin/grep.c
Simple merge

diff --cc builtin/index-pack.c
Simple merge

diff --cc builtin/log.c
Simple merge

diff --cc builtin/ls-files.c
Simple merge

diff --cc builtin/ls-tree.c
Simple merge

diff --cc builtin/merge-base.c
Simple merge

diff --cc builtin/merge.c
Simple merge

diff --cc builtin/name-rev.c
Simple merge

diff --cc builtin/notes.c
Simple merge

diff --cc builtin/pack-objects.c
Simple merge

diff --cc builtin/pull.c
Simple merge

diff --cc builtin/push.c
Simple merge

diff --cc builtin/read-tree.c
Simple merge

diff --cc builtin/receive-pack.c
Simple merge

diff --cc builtin/reflog.c
Simple merge

diff --cc builtin/remote.c
Simple merge

diff --cc builtin/repack.c
Simple merge

diff --cc builtin/replace.c
Simple merge

diff --cc builtin/reset.c
Simple merge

diff --cc builtin/rev-list.c
Simple merge

diff --cc builtin/rev-parse.c
Simple merge

diff --cc builtin/rm.c
Simple merge

diff --cc builtin/show-branch.c
Simple merge

diff --cc builtin/submodule--helper.c
Simple merge

diff --cc builtin/tag.c
Simple merge

diff --cc builtin/unpack-objects.c
Simple merge

diff --cc builtin/update-index.c
Simple merge

diff --cc builtin/verify-commit.c
Simple merge

diff --cc builtin/worktree.c
Simple merge

diff --cc cache.h
Simple merge

diff --cc config.c
Simple merge

diff --cc connect.c
Simple merge

diff --cc convert.c
index 4097f521f240240fde1a3bfa8519515fdaac75f6,69f23cfcaa90993416eaa76303059f3bd389bf9a..7d2a519dafe5dcf892df10c51e1bfb83bc8a2091
--- 1/convert.c
--- 2/convert.c
+++ b/convert.c
@@@ -1,5 -1,5 +1,6 @@@
 +#define NO_THE_INDEX_COMPATIBILITY_MACROS
  #include "cache.h"
+ #include "config.h"
  #include "attr.h"
  #include "run-command.h"
  #include "quote.h"

diff --cc credential-cache--daemon.c
Simple merge

diff --cc diff.c
Simple merge

diff --cc dir.c
index 6687d84dbc8dfb4f6d39028e2b9636278a6146e2,42beb65beaa03dbcf5fb312d7c280a1b3251614b..f6795473f7e52c790605d23628f81e3b295155d8
--- 1/dir.c
--- 2/dir.c
+++ b/dir.c
@@@ -7,8 -7,8 +7,9 @@@
   * Copyright (C) Linus Torvalds, 2005-2006
   *             Junio Hamano, 2005-2006
   */
 +#define NO_THE_INDEX_COMPATIBILITY_MACROS
  #include "cache.h"
+ #include "config.h"
  #include "dir.h"
  #include "attr.h"
  #include "refs.h"

diff --cc environment.c
Simple merge

diff --cc fast-import.c
Simple merge

diff --cc fetch-pack.c
Simple merge

diff --cc git.c
Simple merge

diff --cc grep.c
Simple merge

diff --cc help.c
index 5cdfac7dc20d23089a1230c885dc1701a2caf1ac,b8f3a98e4cbe09dd903dfb86653938c1d7604e3d..8ba0777410bd6377a1325622f7d73a53a0aa5a60
--- 1/help.c
--- 2/help.c
+++ b/help.c
@@@ -1,7 -1,7 +1,8 @@@
  #include "cache.h"
+ #include "config.h"
  #include "builtin.h"
  #include "exec_cmd.h"
 +#include "run-command.h"
  #include "levenshtein.h"
  #include "help.h"
  #include "common-cmds.h"

diff --cc http-backend.c
Simple merge

diff --cc ident.c
Simple merge

diff --cc ll-merge.c
Simple merge

diff --cc log-tree.c
Simple merge

diff --cc mailinfo.c
Simple merge

diff --cc merge-recursive.c
Simple merge

diff --cc notes-utils.c
Simple merge

diff --cc notes.c
Simple merge

diff --cc parse-options.c
Simple merge

diff --cc pathspec.c
index 828405021fca4214585e1d46b65f604d14e61143,e4659b1440c94d0f65ef486a488b604d6195d81c..ecc5331c232ef81f26343fd958a9b66e92a3fa5e
--- 1/pathspec.c
--- 2/pathspec.c
+++ b/pathspec.c
@@@ -1,5 -1,5 +1,6 @@@
 +#define NO_THE_INDEX_COMPATIBILITY_MACROS
  #include "cache.h"
+ #include "config.h"
  #include "dir.h"
  #include "pathspec.h"
  #include "attr.h"

diff --cc pretty.c
Simple merge

diff --cc read-cache.c
Simple merge

diff --cc refs.c
Simple merge

diff --cc refs/files-backend.c
Simple merge

diff --cc remote.c
Simple merge

diff --cc rerere.c
Simple merge

diff --cc sequencer.c
Simple merge

diff --cc setup.c
Simple merge

diff --cc sha1_file.c
Simple merge

diff --cc sha1_name.c
Simple merge

diff --cc submodule.c
Simple merge

diff --cc transport.c
Simple merge

diff --cc unpack-trees.c
Simple merge

diff --cc upload-pack.c
Simple merge

diff --cc wrapper.c
Simple merge

diff --cc xdiff-interface.c
Simple merge