acc name calc for input type=image match browsers better

IE/Edge/firefox use title, if not used as acc description, before supplying own string, so switched order to reflect 
fixes #150

Author: stevefaulkner

index.html

@@ -5544,8 +5544,8 @@ <h4><code>input type="image"</code> Accessible Name Computation</h4>
           <li>If the control  has an <a href="https://www.w3.org/TR/wai-aria-1.1/#aria-label"><code>aria-label</code></a> or an <a href="https://www.w3.org/TR/wai-aria-1.1/#aria-labelledby"><code>aria-labelledby</code></a> attribute the <a class="termref">accessible name</a> is to be calculated using the algorithm defined in <a href="" class="accname">Accessible Name and Description: Computation and API Mappings 1.1</a>.</li>
           <li>Otherwise use <code>alt</code> attribute</li>
           <li>Otherwise use <code>value</code> attribute </li>
+           <li>Otherwise use <code>title</code> attribute</li>
           <li>Otherwise the user agent may provide an <a class="termref">accessible name</a> via a localized string of the phrase &quot;Submit Query&quot;</li>
-          <li>Otherwise use <code>title</code> attribute</li>
           <li>If none of the above yield a usable text string there is no <a class="termref">accessible name</a></li>
         </ol>
       </section>