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/consolidation/config/tests/scripts/scenarios

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+SCENARIOS="symfony2 symfony3 symfony4"
+
+AUTOLOAD_DIRECTORIES='src tests'
+
+platform_php_symfony2='5.4'
+platform_php_symfony3='5.6'
+
+requirement_symfony2='symfony/console:^2.8'
+requirement_symfony3='symfony/console:^3'
+requirement_symfony4='symfony/console:^4'