Add 'relative-ref' DID URL parameter. Fixes #349.

index.html

@@ -901,6 +901,21 @@ <h2>Generic DID URL Parameters</h2>
 <a data-lt="ascii string">ASCII string</a>.
               </td>
             </tr>
+
+            <tr>
+              <td>
+<code>relative-ref</code>
+              </td>
+              <td>
+A relative URI reference according to <a
+data-cite="RFC3986#section-4.2">RFC3986 Section 4.2</a>
+that identifies a resource at a <a>service endpoint</a>, which is selected from
+a <a>DID document</a> by using the <code>service</code> parameter. The
+associated value MUST be an <a data-lt="ascii string">ASCII string</a> and MUST
+use percent-encoding for certain characters as specified in <a
+data-cite="RFC3986#section-2.1">RFC3986 Section 2.1</a>.
+              </td>
+            </tr>
           </tbody>
         </table>