add association css

Author: nicovak

vendor/assets/stylesheets/rails_admin/themes/rollincode/theming.scss

@@ -486,4 +486,10 @@ td.carrierwave_type .img-thumbnail {
   height: 25px;
   line-height: 25px;
   color: #333;
-}
+}
+
+.has_one_association_type {
+  background: #F3F1F1;
+  padding: 25px 15px;
+  margin: 25px 15px;
+}