Bug 1270578 - Add missing space ("editmenu"->"edit menu"). r=IanN

suite/locales/en-US/chrome/common/help/cs_nav_prefs_navigator.xhtml

@@ -145,7 +145,7 @@
 
 <ol>
   <li>Open the <span class="mac">&brandShortName;</span>
-    <span class="noMac">Edit</span>menu and choose Preferences.</li>
+    <span class="noMac">Edit</span> menu and choose Preferences.</li>
   <li>Under the Browser category, click History. (If no subcategories are
     visible, double-click Browser to expand the list.)</li>
 </ol>