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/Fixtures/FooSameCaseLowercaseCommand.php

@@ -0,0 +1,11 @@
+<?php
+
+use Symfony\Component\Console\Command\Command;
+
+class FooSameCaseLowercaseCommand extends Command
+{
+    protected function configure()
+    {
+        $this->setName('foo:bar')->setDescription('foo:bar command');
+    }
+}