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/phpdocumentor/reflection-common/src/Fqsen.php

@@ -38,7 +38,11 @@ final class Fqsen
     public function __construct($fqsen)
     {
         $matches = array();
-        $result = preg_match('/^\\\\([\\w_\\\\]*)(?:[:]{2}\\$?([\\w_]+))?(?:\\(\\))?$/', $fqsen, $matches);
+        $result = preg_match(
+            '/^\\\\([a-zA-Z_\\x7f-\\xff][a-zA-Z0-9_\\x7f-\\xff\\\\]*)?(?:[:]{2}\\$?([a-zA-Z_\\x7f-\\xff][a-zA-Z0-9_\\x7f-\\xff]*))?(?:\\(\\))?$/',
+                $fqsen,
+                $matches
+        );
 
         if ($result === 0) {
             throw new \InvalidArgumentException(