Add CoolSMS PHP SDK, and update Composer dependencies

vendor/coolsms/php-sdk/examples/GroupMessage/example_create_group.php

@@ -0,0 +1,37 @@
+<?php
+/**
+ * #example_new_group
+ *
+ * This sample code demonstrate how to create sms group through CoolSMS Rest API PHP
+ * for more info, visit
+ * www.coolsms.co.kr
+ */
+
+use Nurigo\Api\GroupMessage;
+use Nurigo\Exceptions\CoolsmsException;
+
+require_once __DIR__ . "/../../bootstrap.php";
+
+// api_key and api_secret can be obtained from www.coolsms.co.kr/credentials
+$api_key = '#ENTER_YOUR_OWN#';
+$api_secret = '#ENTER_YOUR_OWN#';
+
+try {
+    // initiate rest api sdk object
+    $rest = new GroupMessage($api_key, $api_secret);
+
+    // Optional parameters for your own needs
+    $options = new stdClass();
+    // $options->charset = 'utf8'; 				// utf8, euckr default value is utf8
+    // $options->srk = '';						// Solution key
+    // $options->mode = 'test';					// If 'test' value. refund cash to point
+    // $options->delay = 10;					// '0~20' delay messages
+    // $options->force_sms = true;				// 'true or false' always send sms 
+    // $options->app_version = '';				// App version
+
+    $result = $rest->createGroup($options);
+    print_r($result);
+} catch(CoolsmsException $e) {
+    echo $e->getMessage(); // get error message
+    echo $e->getCode(); // get error code
+}