Elastic: Add chat icon for taskmenu and prefs section entries

skins/elastic/styles/widgets/lists.less

@@ -335,6 +335,9 @@ html.ie11 .listing.iconized li a:before {
     &.calendar > td.section:before {
         content: @fa-var-calendar;
     }
+    &.chat > td.section:before {
+        content: @fa-var-comments;
+    }
 }
 
 /* selecatable list: e.g. spellcheck language selection */

skins/elastic/styles/widgets/taskmenu.less

@@ -59,6 +59,9 @@
         &.notes:before {
             content: @fa-var-sticky-note;
         }
+        &.chat:before {
+            content: @fa-var-comments;
+        }
     }
 
     @media screen and (max-width: @screen-width-xs) {