Ruby

Introduce URI::File to handle file URI scheme

• the default value of URI::File's authority is "" (localhost).
  Both nil and "localhost" is normalized to "" by default.
• URI::File ignores setting userinfo and port
  [Feature #14035]
  fix https://github.com/ruby/ruby/pull/1719
  fic https://github.com/ruby/ruby/pull/1832

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62767 b2dd03c8-39d4-4d8f-98ff-823fe69b080e