added php download of membershipments

vendor/illuminate/contracts/Support/DeferringDisplayableValue.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Illuminate\Contracts\Support;
+
+interface DeferringDisplayableValue
+{
+    /**
+     * Resolve the displayable value that the class is deferring.
+     *
+     * @return \Illuminate\Contracts\Support\Htmlable|string
+     */
+    public function resolveDisplayableValue();
+}