Merge branch 'ah/doc-updates' into maint

Doc updates.

* ah/doc-updates:
  doc: fix formatting in git-update-ref
  doc: fix indentation of listing blocks in gitweb.conf.txt
  doc: fix descripion for 'git tag --format'
  doc: fix inappropriate monospace formatting
  doc: fix ASCII art tab spacing
  doc: clarify boundaries of 'git worktree list --porcelain'

diff --cc Documentation/git-update-ref.txt
Simple merge

diff --cc Documentation/git.txt
Simple merge