Add pear modules, mail and net_smtp via composer (#93)

Add pear modules, mail and net_smtp via composer, remove php 5.6 build due to phpunit 6

lib/composer/vendor/symfony/console/Tests/Helper/HelperTest.php

@@ -11,9 +11,10 @@
 
 namespace Symfony\Component\Console\Tests\Helper;
 
+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Console\Helper\Helper;
 
-class HelperTest extends \PHPUnit_Framework_TestCase
+class HelperTest extends TestCase
 {
     public function formatTimeProvider()
     {