Merge branch 'ja/doc-synopsis-markup'

The way AsciiDoc is used for SYNOPSIS part of the manual pages has
been revamped.  The sources, at least for the simple cases, got
vastly pleasant to work with.

* ja/doc-synopsis-markup:
  doc: apply synopsis simplification on git-clone and git-init
  doc: update the guidelines to reflect the current formatting rules
  doc: introduce a synopsis typesetting

diff --cc Documentation/CodingGuidelines
Simple merge

diff --cc ci/install-dependencies.sh
Simple merge