Reword description for use of label in about page

Author: MarkRobbo

src/main/resources/templates/about.html

@@ -90,8 +90,8 @@ <h2>Conceptual Identifiers</h2>
                Generic and uninformative names such as <code>result</code> or <code>input</code>/<code>output</code>
                should be avoided</p>
             <p class="why">Helpful identifiers allow for the links between steps in the CWL file to be easily distinguished</p>
-            <p class="use">Identifiers are displayed in the tables and are unique to the step. If <code>label</code> or
-               <code>doc</code> strings are for some reason not provided, the IDs will be used in the visualisation</p>
+            <p class="use">Identifiers are displayed in the tables and are unique to the step. The <code>label</code> is also
+            used as a replacement for the identifier in the visualisation if provided.</p>
 
             <h2>Format Specification</h2>
             <p class="recommendation">The <code>format</code> field should be specified for all input and output <code>File</code>s</p>