Documentation - dl-horizontal - no border

[duboisp]

Document the feature .brdr-0 for .dl-horizontal in:

• http://wet-boew.github.io/wet-boew-styleguide/v4/design/lists-en.html#horizontal
• http://wet-boew.github.io/wet-boew-styleguide/v4/design/borders-en.html

This new style will be introduced by PR https://github.com/wet-boew/wet-boew/pull/7995

[duboisp]

PR submitted with adding docs in http://wet-boew.github.io/wet-boew-styleguide/v4/design/lists-en.html#horizontal