Merge branch 'jk/no-more-self-assignment'

This started as a topic to reduce "type var = var" self assignment
tricks that were used to squelch "variable used uninitialized perhaps?"
warning from some compilers, but resulted in rewriting logic with
a version that is simpler and easier to understand for humans.

* jk/no-more-self-assignment:
  match-trees: simplify score_trees() using tree_entry()
  submodule: clarify logic in show_submodule_summary
Merge branch 'bk/document-commit-tree-S'

* bk/document-commit-tree-S:
  commit-tree: document -S option consistently
Merge branch 'sw/safe-create-leading-dir-race'

* sw/safe-create-leading-dir-race:
  safe_create_leading_directories: fix race that could give a false negative
Merge branch 'tb/cygwin-shared-repository'

Cygwin port has a faster-but-lying lstat(2) emulation whose
incorrectness does not matter in practice except for a few
codepaths, and setting permission bits to directories is a codepath
that needs to use a more correct one.

* tb/cygwin-shared-repository:
  Make core.sharedRepository work under cygwin 1.7
Merge branch 'tr/log-tree-optim'

Optimize "log" that shows the difference between the parent and the
child.

* tr/log-tree-optim:
  Avoid loading commits twice in log with diffs
Merge branch 'js/log-gpg'

Teach "show/log" honor gpg.program configuration just like other
parts of the code that use GnuPG.

* js/log-gpg:
  log: read gpg settings for signed commit verification
Merge branch 'jk/config-with-empty-section'

Document that "git config --unset" does not remove an empty section
head after removing the last variable in a section, and adding a
new variable does not try to reuse a leftover empty section head.

* jk/config-with-empty-section:
  t1300: document some aesthetic failures of the config editor
Update draft release notes to 1.8.3

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'master' into next

* master:
  Update draft release notes to 1.8.3