Use the minimum number of rows for navbar items

issue9625
review294531002

src/sao.less

@@ -71,6 +71,12 @@ html[theme="default"] {
     }
 }
 
+.navbar-nav {
+    @media (min-width: @grid-float-breakpoint) {
+        float:none;
+    }
+}
+
 .btn-primary {
     .icon {
         filter: brightness(0) invert(1);