``<abbr>`` with title also useful for AT

...and remove the redundant paragraph for basic abbreviation, which
simply repeats what was just said above.

docs/_includes/css/type.html

@@ -220,10 +220,9 @@ You can use the mark tag to <mark>highlight</mark> text.
 
   <!-- Abbreviations -->
   <h2 id="type-abbreviations">Abbreviations</h2>
-  <p>Stylized implementation of HTML's <code>&lt;abbr&gt;</code> element for abbreviations and acronyms to show the expanded version on hover. Abbreviations with a <code>title</code> attribute have a light dotted bottom border and a help cursor on hover, providing additional context on hover.</p>
+  <p>Stylized implementation of HTML's <code>&lt;abbr&gt;</code> element for abbreviations and acronyms to show the expanded version on hover. Abbreviations with a <code>title</code> attribute have a light dotted bottom border and a help cursor on hover, providing additional context on hover and to users of assistive technologies.</p>
 
   <h3>Basic abbreviation</h3>
-  <p>For expanded text on long hover of an abbreviation, include the <code>title</code> attribute with the <code>&lt;abbr&gt;</code> element.</p>
   <div class="bs-example" data-example-id="simple-abbr">
     <p>An abbreviation of the word attribute is <abbr title="attribute">attr</abbr>.</p>
   </div>