Add support for inline form in nav-controls component

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/stylesheets/framework/nav.scss

@@ -85,6 +85,10 @@
       display: inline-block;
     }
 
+    > form {
+      display: inline-block;
+    }
+
     input {
       height: 34px;
       display: inline-block;