Changed placeholder to support IdTextPair

select2/select2-tests.ts

@@ -9,6 +9,9 @@ $("#e2").select2({
 $("#e2_2").select2({
     placeholder: "Select a State"
 });
+$("#e2_3").select2({
+    placeholder: { id: "1", text: "Select options" }
+});
 $("#e3").select2({
     minimumInputLength: 2
 });

select2/select2.d.ts

@@ -42,7 +42,7 @@ interface Select2Options {
     minimumInputLength?: number;
     minimumResultsForSearch?: number;
     maximumSelectionSize?: number;
-    placeholder?: string;
+    placeholder?: string | IdTextPair;
     separator?: string;
     allowClear?: boolean;
     multiple?: boolean;