Merge tag 'v2.8.0'

Merge tag 'v2.8.0'

Git 2.8

* tag 'v2.8.0': (532 commits)
  Git 2.8
  Documentation: fix git-p4 AsciiDoc formatting
  mingw: skip some tests in t9115 due to file name issues
  t1300: fix the new --show-origin tests on Windows
  t1300-repo-config: make it resilient to being run via 'sh -x'
  config --show-origin: report paths with forward slashes
  submodule: fix regression for deinit without submodules
  l10n: pt_PT: Update and add new translations
  l10n: ca.po: update translation
  Git 2.8-rc4
  Documentation: fix broken linkgit to git-config
  Documentation: use ASCII quotation marks in git-p4
  Revert "config.mak.uname: use clang for Mac OS X 10.6"
  git-compat-util: st_add4: work around gcc 4.2.x compiler crash
  l10n: vi.po (2530t): Update translation
  l10n: zh_CN: review for git v2.8.0 l10n round 2
  gitk: Follow themed bgcolor in help dialogs
  gitk: fr.po: Sync translations with git
  gitk: Update French translation (311t)
  gitk: Update German translation
  ...