Add colored borders.

services/web/public/stylesheets/app/editor/review-panel.less

@@ -66,6 +66,14 @@
 	background-color: #FFF;
 	max-width: 148px;
 	word-wrap: break-word;
+
+	&-insert {
+		border-left-color: @rp-green;
+	}
+
+	&-delete {
+		border-left-color: @rp-red;
+	}
 }
 
 .has-review-panel {