Ruby » Ruby master

merge revision(s) 58410,58411: [Backport #13487]

    ri.1: rewrite ri man page

    * man/ri.1: update the (very outdated) ri man page:
      * update document date
      * fix document title formatting and volume name
      * update descriptions and options to current ri --help text
      * fix some mdoc formatting errors (missing escaping of `\',
        wrong macro for bullet list items)
      * various rewordings and other improvements

    improve man pages

    * man/ruby.1, man/erb.1, man/goruby.1, man/irb.1:
      fix document title formatting and volume name,
      improve "REPORTING BUGS" section: fix mdoc formatting error
      (wrong macro for bullet list items), small rewordings.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@62132 b2dd03c8-39d4-4d8f-98ff-823fe69b080e