Merge branch 'vh/config-interactive-singlekey-doc' into maint

* vh/config-interactive-singlekey-doc:
  git-reset.txt: better docs for '--patch'
  git-checkout.txt: better docs for '--patch'
  git-stash.txt: better docs for '--patch'
  git-add.txt: document 'interactive.singlekey'
  config.txt: 'interactive.singlekey; is used by...

diff --cc Documentation/config.txt
Simple merge

diff --cc Documentation/git-add.txt
Simple merge