Remove obsolete sentence

> @peacekeeper  wrote: this is a remnant of the version of the spec that had matrix parameters. I think the sentence should simply be removed.

fixes #353

index.html

@@ -945,12 +945,6 @@ <h2>Generic DID URL Parameters</h2>
 RDF / JSON-LD documents.
         </p>
 
-        <p>
-DID parameters SHOULD NOT be used if there are already other, equivalent ways of
-constructing URIs that fulfill the same purpose (for example, using other
-syntactical constructs such as URI query strings or URI fragments).
-        </p>
-
         <p>
 DID parameters SHOULD NOT be used if the same functionality can be expressed by
 passing options to a <a>DID resolver</a>, and if there is no need to construct a