add mark unread icon

templates/partials/post_bar.tpl

@@ -19,7 +19,9 @@
 		<!-- IMPORT partials/topic/watch.tpl -->
 
 		<!-- IF loggedIn -->
-		<button component="topic/mark-unread" class="btn btn-default">[[topic:mark_unread]]</button>
+		<button component="topic/mark-unread" class="btn btn-default">
+			<span class="visible-sm-inline visible-md-inline visible-lg-inline">[[topic:mark_unread]]</span> <i class="fa fa-inbox"></i>
+		</button>
 		<!-- ENDIF loggedIn -->
 
 		<!-- IMPORT partials/topic/sort.tpl -->