Minor change to help documentation.

org.lamport.tla.toolbox.doc/html/model/about-models.html

@@ -59,7 +59,7 @@ or typing <code>Control+Shift+A</code>.&nbsp;  This raises a window showing the
 and the beginning of their <em>Model Description</em> fields.&nbsp;  Double-clicking
 on a model opens it.&nbsp; 
 You can also open
-imported modules from that window.
+imported modules from that window.&nbsp;  Check out the window's <em>options</em> menu.
 </p>
 
 <p>