Require phpunit 6.5 or greater so we don't need shim.php to set legacy class name aliases which are included in phpunit/php-mock-objects (6.5.0 ~ 7.2.0) or in phpunit/phpunit (since 7.2.0)

Author: zebraf1

.travis.yml

@@ -1,7 +1,6 @@
 language: php
 
 php:
-  - 5.6
   - 7
   - 7.1
   - 7.2

composer.json

@@ -10,6 +10,7 @@
         }
     },
     "require": {
-        "codeception/phpunit-wrapper": ">6.0.15 <6.1.0 | ^6.6.1 | ^7.7.1 | ^8.0.3"
+        "codeception/phpunit-wrapper": "^6.6.1 | ^7.7.1 | ^8.0.3",
+        "phpunit/phpunit": ">=6.5 <9.0"
     }
 }

src/Stub.php

@@ -1,8 +1,6 @@
 <?php
 namespace Codeception;
 
-require_once __DIR__ . DIRECTORY_SEPARATOR . 'shim.php';
-
 use Codeception\Stub\ConsecutiveMap;
 use Codeception\Stub\StubMarshaler;
 use PHPUnit\Framework\MockObject\Generator;

src/Stub/Expected.php

@@ -2,8 +2,6 @@
 
 namespace Codeception\Stub;
 
-require_once __DIR__ . DIRECTORY_SEPARATOR . '..' . DIRECTORY_SEPARATOR . 'shim.php';
-
 use PHPUnit\Framework\MockObject\Matcher\InvokedAtLeastOnce;
 use PHPUnit\Framework\MockObject\Matcher\InvokedCount;