refactor(legacy): clean config

- sort imports
- improve indentation
- rename internal_values to legacy_values
- reorder functions
 remove unused isYesValue

legacy/tests/application/configs/ConfigTest.php

@@ -1,23 +0,0 @@
-<?php
-
-/**
- * @internal
- * @coversNothing
- */
-class ConfigTest extends PHPUnit_Framework_TestCase
-{
-    public function testIsYesValue()
-    {
-        foreach (['yes', 'Yes', 'True', 'true', true] as $value) {
-            $this->assertEquals(Config::isYesValue($value), true);
-        }
-
-        foreach (['no', 'No', 'False', 'false', false] as $value) {
-            $this->assertEquals(Config::isYesValue($value), false);
-        }
-
-        foreach (['', 'anything', '0', 0, '1', 1, null] as $value) {
-            $this->assertEquals(Config::isYesValue($value), false);
-        }
-    }
-}